What's the movie about the young girl and her family who move in with a painter?

Ok, I can't for the life of me remember the title of this movie, but I
know most of the plot. There's a poor woman with two daughters, one
outspoken and confident, the other mentally challenged. They sell
apples. The family ends up moving in with a painter where one of the
girls becomes his assistant. There's this spoiled rich girl who
eventually becomes friends with the painter girl. She has her portrait
painted, and for some reason I think her dad is rich because he sells
a rare type of flower or something.

I swear it's a real movie! Google just hasn't been much help. It keeps
giving me "Girl with the Pearl Earring." A fine movie, but not the one
I'm looking for. Thanks for helping!