This was a library book I read as a 11-13 year old, in the early eighties. It had probably been published in the seventies.
It was about a girl who I think was named Daisy, who I think was 14. Her family summered at the same beach every year and she had three special friends, two boys and another girl, she did everything with every year.
Only this year the other girl has “developed” and Daisy (or whatever her name was) hasn’t and the boys pay all the attention to the other girl and nothing is like it was before.
But, also vacationing there is a handsome painter who’s all the rage, and he asks to paint Daisy. The cover of the book is supposed to be his painting of her.
I believe it’s called “The Cheese Stands Alone”. I read it, at any rate. Her nickname was Dosy, not Daisy. There were three other boys, not two: one of them was called Uno, because he was numero uno among them, and she was numero dos. Until the other girl developed and Dosy became numero zero.
Thanks Rilchiam! I think that is it! The Numero Uno, Numero Zero stuff rings a bell. I checked it out at the library of congress site (which incidentally says her name is Daisy) and it sounds right. Now to get my hands on it. My library doesn’t have it. Maybe Interlibrary Loan.