After Maverick pulled Bradley "Rooster" Bradshaw's papers and also having resentment towards his dad's (Goose) death and Bradley didn't talk to Maverick for years but after Top Gun and a near-death experience things changed

After Rooster and Maverick reconnect there relationship was far from perfect and they still had things to work on but it was getting better

Bradley then soon became a father

Now you were 2 years old and Bradley needed someone to babysit you and Maverick was available so why not? He watched Bradley all the time when he was Two and he was a pretty good kid so how hard could it be?

Heh...Turns out Bradley was just one of the small minority of 2-year-olds that weren't little terrors

You were just crying/whining because you wanted your dad

Maverick just sighed as he picked you up "Hey, Baby Roo you need to chill out"