Book about girl named Charity who does watercolours? ?

I read this book once about a girl named Charity (I'm 99% sure that was her name). I remember she did watercolour paintings for children's books in the story, and the book described her nursery when she was a baby. I believe she was an only child and was around adults a lot as a kid. 

Anyway, the closest thing I've found to it is Charity by Lesley Pearse. The book description doesn't tell me much about the story I remember, so to those who have read it, is it the same book?

If not, who's the author of the book I remember?