Book with baby twins in it for older siblings.

[~bookcase~]

http://www.amazon.com/Cat-Sitter-Mystery-Carol-Adorjan/dp/0595140874/ref=sr_1_7?s=books&ie=UTF8&qid=1322002807&sr=1-7

We are reading this at the moment and it's great for siblings 7+ who have baby/ toddler twins.

The story is about a girl who moves to a new neighbourhood and babysits some cats, but there are a few references to the twins and her having to look out for them, watch them etc