My toddler loves this book. We talk about the baby in mommy's belly all the time. We look at the book together and I tell her what the baby is doing and what the big girl (even though it looks like a boy in the book) is doing. Then we look at it and I have her point to the baby. Great book for new siblings!
This is a simple board book. There are no words which is a little weird, but it's good that you can make up your own words to fit your family. My son is almost 3 and will be a big brother soon. He enjoyed looking through this, but prefers his wordier big brother book. I am thinking this might be a better book for younger tots.