I'm not a fan of nicknames personally - even though my own name get shortened all the time from K.elly to K.el - so I decided to give my kids short names to hopefully avoid the nickname thing happening.

DD, T.ara and DS2 L.iam have no issue as there names are hard to add or subtract extra letters from by DS1 R.hys has been called R.hysy from day 1, but I think that is more because his brother and sister have 2 syllables in their names and his is only 1. But I've started to be more conscious of using his correct name but it doesn't bother me which one gets used as I know when he gets older the baby name version will get dropped IYKWIM.

My opinion is if you like a name then you make sure everyone using the pronunciation you choose - it's not up to anyone else to make a new name. I would tell them his name is ..... not .....