I don’t think you are confused at all. @conmama
Yes, advice as to what to say and reassuring her. I think her concerns are unfounded. I don’t think Bob is interested in mil’s, “stuff.” Sil had expressed concerns about the stuff over three days before I came here to CC.
The things she eventually wants that mil is taking to the CCRC:
- Rings
- Oak table
- Mil’s silver (plate) flatware
- Signed prints by Donald Roller Wilson
Sample texts (of several):
“I think when we are packing up the Rollers, I plan to say that I really don’t expect to ever see them again if she goes first. Cruel but true.”
“I’m going to ask her where her rings are. I wish she’d give them to brother or me. Things get stuffed in Bob’s house. They will disappear.”
“I’m going to have to go up there with the police and the pre-nup if she goes first.”
It’s borderline irrational to me. It’s fear for her mother and their future relationship being redirected through these things.
Before I ever came here to CC I told her:
- You need to tell mil what you want so she can tell Bob.
- Pre-nup won’t help because personal property isn’t enumerated. She can make a holographic codicil to get will.
- I have told dh what you want. You are not alone. He will be there with you.
- This conversation can happen organically while you are going through the house.
Nothing is helping because it’s not about the things/stuff. It’s about her feeling abandoned by her mother!
I guess I was coming HERE to vent. Nothing I say is reassuring her. Her approach with her mother is, IMO, too antagonistic.
Dh knows all of this, and he and mil have a three-hour car ride together. He, too, thinks sil is overreacting. She will be there when they arrive and she and dh can have a convo while mil goes to get her hair done.
Everyone has been IMMEASURABLY helpful here in confirming that I’ve said all I can say. I cannot fix this.
Below is one of the prints mil has that sil fears will never be returned. When I asked ds if there was anything from his grandmother’s house he wanted he said, “Well, not any of those creepy monkeys.” 
She has at least three. At least one is signed. They’re just prints - not originals