Hogwarts returned to normal, and Professor McGonogall was headmistress till the end of her days. Harry became an auror, Hermione was minister(think that's right) of magic. And the wizarding world had never had a better minister in years. Ron took over his father's job. Neville was the biology teacher and  Stella the DATDA teacher. Harry and Ginny and Ron and Hermione had a double wedding and their kids. Neville and Stella got married. (They had two children, Helena Rose and Demetrius Longbottom. The trio had their kids.

And the four  Gryfindors remained friends till the end of their days.

The end.