SOLVED. 1980s children's book - main character Rowena - rescuing town's happiness/laughs [s]

[Heather]

I had a book as a child that involved a main character named Rowena. In the book, a witch (I think?) had stolen all of the happiness/laughter from Rowena's town, and locked it up in a castle or tower or something, so everyone in the town is sad and unhappy. Rowena sets out on a journey and is ultimately able to open the door where the laughter has been locked up, letting it out and restoring the happiness to her town. ???

[Holly]

I Can Read about Witches by Robyn Supraner

[Heather]

Oh my god, that's it - I've been trying to remember the name and find the book for YEARS! Thank you!!! (And I'm curious, how did you know??)

[Holly]

I searched on Worldcat :]