How does this work

[mummy2twobabies]

I've decided on a name for dd2 that's due in 8 week I'm calling her Eliza but I want her name on her bc to be Elizabeth so if she wants to change it to a different nn when she is older she can. How does it work with school and official documents and things.
I'm going to introduce her to family and friends as Eliza and only putting Elizabeth on bc (the name means a lot to me)

My nephew is Richard (known as Richie).
On his name tag books ect and register.Hes Richard, but referred to as Richie. They use their full name so that they get used to it for future documents ect ,My sister just filled In a form and stated he's Richard known as Richie.
A little girl in my dd's year. Her real name was Laura, but she called herself Bobbi as did the school, her friends and her parents.

To me Eliza and Elizabeth are two different names.

I don't get this weird obsession on MN with nicknames? To me a nickname is something organic? If you want child to be called Eliza then call her Eliza?

Sorry but it's a pet hate of mine.

In my experience, when my daughter started pre-school the forms had a space for full name and preferred name. i work as a children's nurse and the admission paperwork at our hospital also has a section for "likes to be known as". When I spent some time working with the elderly in my training I met lots of old people who liked to be known as an entirely different name unrelated to their legal name - eg Edmund Bloggs known as Fred, so I think most institutions are used to this.

Thank you for the replies. I want her name to me Elizabeth which is a long name for a young child. I will introduce her to family as her Eliza because that is the nn I want her to have opposed to using Beth or Lizzy or such. My ds has a name that was meant to me shortened to a nn but only I call it him and he was born well before I joined mn so it's definitely not a just an mn obsession. I just wanted to know how it works at school and office documents. Thank you for helping answer my question.

SweetTeaVodka my grandad was the same I didn't find out that he had a completely different name as the one on his bc until after his death. As far as I know it never caused him any problems as far as I know but I obviously can't ask him. My Nans name was Elizabeth but she was known as Betty.

All my dses have short names they are known as. On forms etc, particularly school forms so they have the right name there I just write Edward James Smith known as Teddy. It has never been a problem.