I bought this (and sneakily read it) to send to my cousin. They've just had their second child and I think it important that the older sibling doesn't feel left out (I know I did when my baby brother came along and ruined my perfect little world - that's not entirely in jest). In this Topsy & Tim's friend Toby gets a little brother. So there's pregnancy, then when they visit they discover that babies cry, need their nappy changing and need to be treated gently. Not too much detail, but at least a way for a sibling to understand what's going on.
I selected this over the Peppa Pig equivalent as I remember Topsy & Tim from my childhood, so there was a spot of a nostalgia trip going on here. ( )