I first heard of her in late 1975 or 1976, given the date of a certain Avon edition. See here:

"ID this pre-1980 novel - woman with menagerie?"

https://groups.google.com/g/rec.arts.sf.written/c/fXWXVfYfVMA/m/-Uzf600FBAAJ

It turned out to be what is probably her most popular book.

Since my memory wasn't quite clear, I confused the style of the cover artist - Gervasio Gallardo - with Brian Froud's style.

But, somewhat ironically...

https://locusmag.com/2022/05/patricia-a-mckillip-1948-2022/

"Other books (of McKillip's) include non-SF children’s book The Night Gift (1976); adult contemporary novel Stepping from the Shadows (1982); shared-world novel Brian Froud’s Faerielands: Something Rich and Strange (1994), a Mythopoeic Award winner...
"

(snip)

"About The Night Gift:

"What does it mean to give love, and to receive it? No one can answer. For the answer can only be lived. And sometimes, the living takes sharp and unexpected turns.

"It seemed so simple to Barbara, Joslyn and Claudia -- the idea that they would make beautiful a room in an old abandoned house for Joe Takaota. He was Barbara's brother, and he had tried to take his life because, he said, 'It's so ugly.' If they could
give him a beautiful place, now that he was coming home from the hospital, maybe he would be all right. They worked on it at night, and soon each found the room invading her life in ways she had not expected..."

http://patriciamckillip.com/
(her site)

https://www.youtube.com/watch?v=7pbcEwY9LoM
(interview - 3:05 minutes - this seems to be the only such video)

https://www.publishersweekly.com/pw/authorpage/patricia-a.-mckillip.html
(PW reviews)

https://www.kirkusreviews.com/author/patricia-a-mckillip/
(Kirkus reviews)

https://www.goodreads.com/author/show/25.Patricia_A_McKillip
(reader reviews)

https://www.fantasticfiction.com/m/patricia-a-mckillip/
(book covers)

http://patriciamckillip.com/novels/
(bigger book covers, from newest to oldest)

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