I thought I'd remember her saying it was going to be, and yes I was wondering about that. Especially since the ending doesn't seem like it was adapted for anything that happened after book 1.
Ms. Rowling knew she'd need to create a baby named "Teddy" sometime, and she'd need a plausible relation between a Weasley and someone French; but further details would be unimportant. When Nymphadora's dad entered later on, he was named so his grandson could meet the requirement. And of course Fleur could barry Bill.
Really, what information is there in the epilogue that isn't in Book 1?
While there were a few details in later books which were made to fit the ending, the ending ignores the later books. When Ms. Rowling wrote the ending, she probably had no idea that there would be a Luna Lovegood, nor a Nymphadora Tonks, nor Sirius Black, Remus Lupin, Delores Unbridge, et al. Consequently, all those characters are effetively ignored.
Teddy was Remus and Tonk's baby; named after her father, Ted.
Really, what information is there in the epilogue that isn't in Book 1?
A poster on this thread yesterday said that he re-read Book 1 after Book 7 and that everything in Book 7 is completely set up in Book 1.
Interesting.
Maybe on some of them, but Hagrid brought Harry to the Dursley's riding the motorcycle he borrowed from "Young Sirius Black."
The last WORD may not have been scar, but the last sentence was about how his scar had not hurt since Voldemort died.