I’m still confused about what kind of insider info OP has … The couple knows that he has leukemia. Why do you think there’s been a turn for the worse that is unknown to the kids?
To me this sounds like “why the hell aren’t you getting married now? It’s been long enough.”
That may not have been your intent, but that’s what it sounds like.
Please, stay out of it. Weddings can be stressful enough without any outside pressure- even if well-meaning.
How do I know that the parent status has changed? When diagnosed he had oral chemo. Now twice a month of infused of chemo. Stronger oral drugs. Exhaustion
Thanks for answering. Is there a reason you think his dd doesn’t know about the change?
FWIW my MIL nudged my DH to pop the question. I think he would have sooner or later, but he was in the midst of preparing for his thesis defense and looking for post-docs and I don’t think was focused on the fact that some of the post-doc plans (i.e. going overseas) would work better if we were actually married. We’ve been married since 1984 so I don’t think MIL’s nudge was a problem.
Anyway, I think it might be okay to say something, but think carefully how to say it.
I’d personally stay out of it. If the young adults want to confer with the patient, nothing is stopping them that has been presented. If they are content with things as they are, it’s their lives and intervention by you or anyone else may be very unwelcome, especially if treatment has increased as described.
@bevhills I assuming that your son is the groom? You know your own family. How family’s operate are greatly different based on many things including culture. My friends who are Columbian and my sister’s family who are Italian are probably two of the tightest families I’ve ever met and just everything is discussed and talked about openly and they work together in a very synergistic way. For some family’s marriages are intensely private decisions between a couple and for some they are family affairs. You know the kind you have.
In our family, if we had @LeastComplicated 's scenario in which the eldest son told everyone to wait and then it was top late… First of all, my sister would completely ignore him and get on the plane the next day. But that would be very, very hard for people to get over. @LeastComplicated 's update was intuitive and meaningful. We err on the side of panic and worry. We are all projecting. Not knowing your family. I only know that within our family if someone didn’t share important information like this health change and people found out later would be hurt feelings.
The day my father died, he was volunteering at a charity golf event and spent the afternoon talking the person he was riding in the golf cart with about the weddings of his three children. I wonder if he knew a bit if something was going to happen. There was no warning. His heart failed as he drove home but he managed pull over without hurting anyone. My mom is different but those were really important moments for him.
And just one last thing about those fragile moments. The last time I saw my dad was a special family event for my family. I remember being irritated that my parents were late. But they got there in the knick of time and we treated them to a nice dinner. And my boys danced for them and my father couldn’t stop laughing. I really regret being irritated but the happy end of the day helped me through. We don’t always think about how fragile life is even as adults. If this is your future daughter in law and that is her father, to again see this through my family’s lense, changing a wedding date would be nothing as opposed to not having that person there. My sister would have been crying the whole wedding day and not really ever get over it. That is how my family would see it. And I respect that all families are different and you know your family.
Lastly, I’m so sorry that your family is going through this difficult time.
Every situation is different. My DD and fiancé were engaged to be married in May 2016. In January 2016, my husband was diagnosed with a rare and aggressive cancer. In March 2016, he was hospitalized, and DD and I were told he probably wouldn’t survive more than a few days more. The oncology team told DD if she wanted her dad to be part of her ceremony, she might consider getting married ASAP. They didn’t waste any time making arrangements. The oncology team’s social worker played the part of wedding coordinator, DD and her fiancé flew his mother in from Virginia, the oncology nurses arranged for a reception area with decorations, and the hospital chaplain officially married them in the atrium of the critical care tower with hubby’s oncology and renal teams in attendance. My husband was able to stand on a walker with me at his side long enough to give DD’s hand to our son-in-law. My husband beat the odds and was discharged after a 21-day hospital stay. DD and her husband were married again in May at their originally-scheduled celebration and my husband was able to make that celebration, too, but was extremely weak. We were so happy that he was able to celebrate with us twice.
If the couple getting married know the severity of the situation, I’m sure they’ll decide what is right for them. If they don’t, it’s because the father doesn’t want them to know, and it wouldn’t be your place to tell.
I hope things work out for all involved, and that treatment is successful, allowing your child’s SO’s father to attend and be involved.
The only thing I’d ever do is ask (while making general convo) how the parents are doing. It’s really none of your business if there’s a health issue or not.
I know you and your warm heart. 
I can understand why you would want to draw the potential implications of the situation to the kids’ attention, especially as a cancer survivor yourself.
I think if I were you I would have a heart to heart with my own child, explain my concern, and suggest that maybe the two of them should talk about it, if they haven’t already. If the SO’s father has been diagnosed for 5 years and is not obviously ill, they may have grown used to the idea that this is a chronic disease and think he’s just going to go on living with it for years. Which may or may not be the case, especially given the apparent progression of treatment.
Having done that, I’d let it go. I think that expressing the concern in a discreet and supportive way is reasonable. Your child and the SO can take it from there.
I also think that some of the accusatory posts are way out of line.
@bevhills You found out from the SO’s family. Perhaps you could ask that person if SO knows. If SO knows then they have already made their choice and the burden of thinking that you know something so important without the couple would be lifted.
Consolation: Thank you…for everything. Our daughter is the potential bride.
How close are these two to his father?
I’ll admit to being a little confused between ‘recently’ learning and knowing ‘from the beginning.’ But I can’t go so far to say it’s none of your business. Your two families are headed for a melding, you’re part of that.
I think it’s fine to have a mother-daughter chat. But more a question than a push. I might want to “open” the chance my D has something to say, but be respectful and end it, without offering an opinion, if she doesn’t.
Not all think an illness is a reason to push up the date. If he recently lost his mother, they may not want to do anything until they feel settled with that. Or they may be secure enough in their commitment to want to make the wedding about that, not about impending death. And you haven’t said anyone yet knows how long he has. Or did I miss that?
So to me, ok to see if your D has anything to say. But I’d caution about projecting, for now.
Your title asked if you should "interfere, " you asked if you should “tell them to hurry up.” I wouldn’t go that far. But if you’re close to your D, I see no issue with a neutral, respectful question.
Best wishes.
I would talk to my own child. I understand your concern that since this man is the only surviving parent, it would be hard for his son to have neither parent at his wedding. And it would be sad for him to miss the pleasure of seeing his son’s wedding. My niece and nephew delayed their weddings, having unreasonably long engagements, imo–one couple was together 10 years, they’d never really dated anyone else, the in-law was in our family picture 7 years before the wedding! Anyway, my mom, who also had a form of leukemia for years, was too sick to travel to the first wedding, and died before the 2nd one took place. My brother also died unexpectedly before my mom–he could’ve also been at those weddings with his family if they had taken place a little earlier.
I’m not sure how old your D is, but if the engagement/wedding are already in the works, I don’t think it would be wrong to talk to your own daughter about this issue. Young people aren’t often considering these things when it comes to planning a wedding. But she’ll need to talk to her SO about his father’s health and find out how ill he actually is.
After reading @SplashMom 's poignant post, all families are different but my dad wasn’t a good communicator. I would not have known his health issues or his concern about attending the wedding. Not that he would consider that private but he wasn’t great a expressing certain things. He completely relied on my mother for that. So like @SplashMom 's situation, he would have relied on his medical team for that communication to his family about both the medical condition and wedding choice if he was a widower. Also, having two ceremonies like that situation could be a problem solver if need be. I had not thought of that but obviously the medical team had experience.
I don’t think you should suffer, @bevhills. A simple chat with DD to discover what they know about dad’s situation. I would also think that it would be fine to express your support for their choices but also your personal concern about the situation. You could be at peace. I would not want my mom to be stressed (especially when dealing with health issues) over something we could chat out in five minutes.
My advice is in line with Consolation’s in that I would tell my dd that I heard from (whoever it was) in so’s family that the dad may be sicker than he appears and that while I am not sure that is true, whether SO had said anything. I know people who have had terminal diseases and did not share the prognosis with their children. If I were the kid and eventually found out that others knew the dad was terminal (if he is) and nobody told me, I would be upset that I was not given the opportunity to move up my wedding or do other things to adjust my life to provide more support to my dad.
I would also talk to whoever told you this (assuming it is more than just going to the oncologist), to find out more.
Agree that telling them to hurry up, based on this limited information, is not the best approach.
I’ve had a form of leukemia for 15 years. I see the oncologist every three months. We have not moved my sons’ universes around because of it.
Does the S know his dad is ill?
I would stay out of it, personally.
Weddings and ceremonies may not be important to the dad. Knowing that his kid is happy in a good relationship while moving steadily and successfully through life may be more comforting to him than seeing a big splashy to-do. Many people find big ceremonies like weddings to be emotionally draining. It might be that the best gift you can give him is the gift of boring normalcy.
If my daughter were in @bevhills ’ daughter’s situation, I most certainly would say that I saw fiance’s dad at the oncologist and was concerned. I don’t think this is nosy or interfering. You have information that your own child might really need to know. This has nothing to do with the wedding unless they want it to, but if my kid’s future father in law were ill, yes, I’d tell her.
@Otterma IDK maybe people don’t talk to each other much anymore but there is no need for speculation. This is a three to five minute conversation.
DM: How is Mr. X? We support any decision you make but I’m concerned…
DD: Don’t worry mom. XYZ