What about the Son

[iyan46]

My wife will soon be applying for citizenship, i have been reading and checking and i have a question that doesn't seem to be addressed ... so maybe someone here can help me.

 

My son will also be applying for citizenship and as i read it he will have to wait until he has been here 5 yrs due to his age ( 19 ) but he also would like to change his name. According to what i read he will have to do this through the courts to make it a legal name change. My question is this ..... he already has his 10 yr green card, will he have to apply for a new green card before he applys for citizenship ? and if so will he have to reapply for his green card first? or if theres a legal name change form that we can fill out?