That reminds me of my first child. When I was carrying him, we chose the name Joseph Aaron, because it means "increaser of brightness". We were going to call him Aaron.
But when he was born, he just didn't "look" like a Joseph Aaron, or an Aaron. We called him that for a few days, but it just didn't feel right.
So, we changed it to Joshua Lynn, and that felt perfect. When he was little, he always corrected everyone that tried to call him "Josh". He would say, "NO! My name is JAH-SHOO-WAH!"