SOLVED. I remember reading a book about four years ago but cannot recall the title. Some things I remember are: [s]

[Alice]

I remember reading a book about four years ago but cannot recall the title. Some things I remember are:

-In a younger sister's point of view. The older sister begins behaving strangely.

-The father calls the older sister "Maxi" and the younger one "Mini"

-Mini befriends a boy at school, who speaks with a stutter

-Maxi's strange behavior is revealed: she was adopted and her birth mother died

-I believe the cover had a butterfly.

[Banjomike]

Do you remember what their real first names were?

[Lisa]

Secrets, Lies And My Sister Kate? There is a cover where a girl has a tattoo of a butterfly on her shoulder.

[Banjomike]

That look like it.

[Alice]

Yes that is it. Thank you and sorry for the late reply

[Lisa]

Great. You're welcome.