Did Neville's parents ever recover

What happened to Gilderoy Lockhart?

in the Order of the Phoenix there is a visit to St. Mungo's Hospital, where they meet Lockhart again. He is still recovering from the effects of the memory charm, but there are signs that his extravagance and love of fame are recovering:

"I feel very good thank you!" Lockhart said exuberantly, pulling a rather battered peacock feather from his pocket. “Well, how many autographs do you want? I can write together now, you know! "

But that's three years after the Chamber of Secrets incident, and according to the nurse on the ward, this seems like a fairly recent development:

"Listen to him," said the healer, taking Lockhart's arm and beaming at him lovingly as if he were a precocious two year old. “He was pretty well known a few years ago. We sincerely hope that this penchant for autographs is a sign that his memory gradually returns . Will you go this way He's in a locked section, you know, he must have slipped when I brought in the Christmas presents, the door is usually locked ... not that he's dangerous! But, "she lowered her voice to a whisper," he's a bit of a danger to himself, bless him ... don't know who he is, you see, wanders away and can't remember how he comes back .. it is nice of you to have come to see him. "

In fact, his nurse describes his condition as permanent:

"This is our long-term resident's station," informed Harry, Ron, Hermione and Ginny in a low voice. "For permanent spell damage, you know."

He's still getting fan mail, too, but he has no idea why. He continues to sign and write to his fans, probably just because he seems to enjoy it. Leftover memories, etc.

"I won't forget, you know, no, I still get a lot of fan mail ... Gladys Gudgeon writes weekly ... I just wish I knew why." He paused, looked a little confused, then beamed again and returned to his signature with renewed vigor.

Although none of these people want to visit the man in person. According to his nurse:

“Oh, Gilderoy, you have visitors! How nice and also on Christmas Day! You know he never gets visitors, poor lamb, and I can't imagine why, he's such a darling, right? "

Finally, JK Rowling confirmed on a Bloomsbury web chat in 2007 that despite some signs of minor recovery, he was likely stuck on that ward for life:

Jessie: Will Lockhart ever recover?

JK Rowling: No. I wouldn't want to either. He's happy where he is and I'm happier without him!

Finally, it should be noted that this only happens in the books. There is a brief post-credits scene for in the films Chamber of Secrets, which enlarges the window from Flourish and Blotts to Lockhart on the cover of a book Wer bin ich? To show. showing him in a straitjacket and mumbling incoherently. No details are given as to whether he wrote the book himself or whether it was written about him by someone else.

Someone uploaded this scene on YouTube: