I was the first-born child, so my mother kept detailed records in my baby book. She called me “Dougie”. 67 years later my wife still calls me “Dougie”. The salesman at the auto dealership laughed when he heard her call me that. We are not in the south, so “Dougie” sounds like a diminutive. I don’t mind, though. I think of it as a term of endearment. Do you have family pet-form names?
“Dougie” (pronounced “DOOgee”) is the usual diminutive for “Douglas” in Scotland. “Doug” (as in England) isn’t often heard.
My wife Siobhan is called “Shiv” by her brothers and sisters, although that makes me think of bright shiny sharp things. Perhaps that’s not wrong… I prefer to call her Bonbon (the other end of the name).
I am Frederick, officially, but Fred, mostly. One or two people call or have called me “Freddy”. I don’t mind. It didn’t really take.
My father was John, but was called Jack by most people. Nowadays, people forget that these are short forms, and name their child “Jack” on official documents. It seems like losing the opportunity for two names, to me. They do the same with “Peggy” - this child could be a Margaret as well!
Benedict becomes Ben. When he was smaller he was “the Beanburger”. We defer to his dignity more now he’s six feet tall.
Niamh is Niamh. Come to think of it, naming your child “brightness” wasn’t a great idea if you are nervous of bright shiny sharp things… But we sometimes call her “Little Dot”. This is more for her enthusiasm for polka-dots - just like the cartoon character, but also…
My Mother was called Dorothea. She might have been Dolly, or Dot. In fact she was Dora. Niamh has startling resemblance to my Mother, who died before Niamh was born. So, “Little Dot” has a deeper resonance.
Our father used the same pet name for all of us: Hey! You!
an’ before Pink Floyd wasn’t it!
Nicknames, 'tis the reason I think Ralfredric would be a great name. You could be called Ralf, Alf, Alfred, Fred, Fredric, Rick, or Cirderflar.
My husband’s name is Jeffrey. I always called him Jeff. The kids and I all sort of spontaneously evolved into calling him Jeffy as his cognitive condition declined. When I think about it objectively it does seem construable as a dis, but I think it’s just more reflective of the actual changes in relationships that occur when someone becomes less aware and more dependent. I can see that in Doug’s case it’s an affectionate diminutive showing intimacy. My version is a way of defining a complete shift in relational status.
Names are whatever you mean them to be.
No one in our family uses pets names with adults, I think we used them with the kids up until they were maybe in the second grade. We do use pet names for our…pets. I use “Mummy” with my mother when I’m being especially sarcastic, does that count?
I’m known as Charles, Charlie, Chas, or Tet, depending on who’s doing the calling. Tet is a nickname my brother gave me when I was about 12 and began my lifelong obsession with tea (short for Tetley). Two of my four siblings go by names I gave them when I was very little and couldn’t pronounce their names. One was even quoted recently in a national magazine going by the nickname she got when I was about 3. My folks were somewhat taken aback by that. Another sib goes by one of those nicknames among the family, but not publicly. Alas, my daughter refuses to be called by a nickname. If I’d known that would happen, I would have lobbied for a shorter name.
For eight years I worked as a bank teller. The bank gave me a name tag with my first name, Robert, although most of my friends and family know me as Doug. Douglas is my middle name. Naturally, customers at the bank called me “Bob”. The only other person in my life who called me Bob was my uncle Jess. It was very confusing. People who knew me would call the bank and ask to speak to Doug, and the other bank employees would say that there was no one here by that name.
I am Russ for Russell. But please not “Rusty” . In high school, ages ago, my party friends called me “RussKrispies” , no comment. Some close friends combine my first (Russ) and last (Cole) names into “Russcle”. My kids called me Daddio when they were young, now they completely ignore me and roll their eyes every time I say something. Can’t list the various terms of reference my wife has for me here on a public forum 
I’ve always just gone by A.J. From the time I was a baby friends, family, even teachers at school all called me that. I guess it doesn’t really count as a nickname since it’s pretty much ubiquitous. About two years ago I moved to Vancouver and decided to try going by my first name, Alan, just for a change of pace. My coworkers found out that I usually go by A.J. at one point and half of them decided they preferred that anyway. I realised I actually preferred that too and that pretty much ended my Alan experiment. Besides, people have a tendency to shorten Alan to Al, which I’ve never cared for. A few have tried shortening A.J. to something that sounds like ‘age.’ I’ve stomped on that pretty quick. Two letters is plenty short enough.
My dad was also Jack for John. My aunt, who is Italian (from Naples), would never believe him. She insisted that his name must have been Giacomo, and had been horribly mangled by some bureaucratic snafu along the way. Picturing my very Irish-looking dad and thinking “Giacomo” causes my head to explode.
The father of my best friend in high school was also Jack. At some point in his 40s he applied for a passport, which required an official copy of his birth certificate. And when the certificate arrived, he was astounded to see that his name was actually Jacob. Apparently, he’d managed a lifetime of official paperwork without ever discovering the discrepancy. Shortly afterwards, my friend converted to orthodox Judaism. Coincidence?
My mother never went by her first name, which is Marjorie. When she got her first passport, well into middle age, she found out that her first name on her birth certificate was Mary. She has no other ID with her nominal first name, which was never a problem before 9/11, but since then, she might as well be a terrorist based on the way she’s treated in airports.
True story-- I had an elderly patient in a nursing home named Ulysses K (lastname), but all the nurses called him Dick. With the name Ulysses and initial K (never did find out what that stood for), I asked him why people called him Dick. He told me that he had many brothers and sisters and at dinner time the table was crowded and noisy. One night his father wanted the butter or some such thing and in the confusion fumbled for U.K.'s name “ummm…Dick, pass me the butter”. From that moment the name stuck and his family and friends never called him anything else. 
My name is Regis, my family has never called me anything else. Occasinally people pop into my life that call me Rege but eventunally they go with Regis. The only nickname that all people come up with for me, no matter where I lived and no matter where they knew me from (work, school, whatever) is Mister Regis. Even when I was young man, that was the nickname. It must fit.
My mom’s name is Elizabeth. When she was born, her father was away prospecting for oil in South America. His name was Theron. He got home when she was a few months old, and informed his wife that little Elizabeth was going to be called ‘Teedy’. He would give no reason, but his word was law, I guess, and the name stuck. Mom is now almost 90 and has been known as Teedy all her life. My sister has a theory that when Theron was working with his buddies after becoming a father, he thought of her as ‘Theron’s daughter’ and shortened that to ‘T.D.’ By the time he got home and met her, he thought that made a good name. I like it too, and we all like the mystery.
I don’t think we have any nicknames in our family, unless you count normal “shortening” of names. Such as how my first name is William, but I go by Will.
However, I do have 3 older brothers and I have been called by their name at least once each by both parents. 
Will, as people often will do, they add a syllable to a name to make it 'cute". I was very close to a friend’s child as he was going up. The boy referred to me as “Dougo”. If someone were to call you “Willy”, would that sound OK and be alright with you?
That depends on their gender and age… 