My dad still uses a silly name for me. I don’t think he realizes it’s silly, it’s just what he’s always called me. I’m just thankful he is still around at almost 80 years of age. He has chronic leukemia that is successfully controlled by meds. That wouldn’t have been the case just a couple of decades ago.
My son has an English name that isn’t common in the US. He doesn’t know that we know that the girls at school (he is quite popular) have shortened it to the name of a common flower. I occasionally see that someone has scribbled this flowery nickname on his homework or folder. He is now 6 foot tall, has a voice deeper than Isaac Hayes, and is a cool dude athlete. Cracks me up!
My sons in-house nickname is noodles. He loved eating ramen noodles as a kid and the nick name stuck. His close friends no about his nickname but he will kill you if you say it around strangers.
Ambrose? Lol. (You don’t need to respond due to privacy)
when they were babies/toddlers, not now.
Wife and I don’t have kids yet, but i do have nicknames for her and for our dog.
Her nickname is Muffin Bear. (I’m Bagel Chicken, her hasty response to her own nickname…)
Our dog’s name is Bristle (like a broom bristle, with a silent T; it bugs us to no end when people call him, and pronounce his name, Bristol…). I call him Booger.
7 kids–I call them all “Babe” 
(or Baby, Babydoll…) We have a lot of nicknames, and there’s a story behind each one–Peanut Head, Brutus, Hungry Hippo, Ninja, Cypher, Mushroom, Pigpen, Lamb/Lamby/Lambskin, The Cute One, The Bad One, Thing One/Thing Two (two brothers close in age), The Brats (youngest two sisters)
Not a secret, I never use D’s given name unless I mean business. I call her " Lib" 99% of the time. No one else does.
Because my D was so difficult to toilet train, she earned herself the nickname “Smelly”. Every so often it just comes flying out of my mouth LOL. My mother somehow shortened my sons name to “Snake”. I didn’t particularly care for it but she and others occasionally used it to address him.
My oldest is Bug. Started when I was pregnant.
My youngest is Hoover. That one was a nursing maniac - from the second feeding at the hospital on, she would lunge toward me as soon as they brought her into the room. Didn’t use Lamaze breathing during labor since she was a section but needed it for nursing for quite awhile.
My oldest daughter is called Scooter by my husband and I. Came from crawling just not being her thing, she scooted everywhere on her butt until she could walk, so the name started then and has stuck with her. She is 17 now and leaving for college in fall, never seems to say anything or have it bother her if we still call her scooter
@KKmama My daddy’s nickname for me was Bug! I always loved it.
My D is called Sunshine. When she was a baby she was always happy- smiling and gurgling. She was the easiest baby, always happy and smiling. From the time we left the hospital she would sleep from 10 pm to 3am. She would wake up , get changed, eat and then sleep from 4 am to 7 am which was such a drastic change from S who would wake up every hour on the hour.
We called my S zoomer. He was always zooming everywhere. Started walking at 8.5 months and running at 10 months. Later it changed to buster brown, I think because we were reading Dr. Seuss books and we were rhyming everything.