This is a really great kids book, because it is adorable, but the actual events are quite serious. The main character, Flora; SPOILER ALERT
Gets rejected by her family
Witnesses a mass mice massacre (try saying that 5 times fast)
Loses all her siblings
Has a father with a missing tail and an injured ear, acquired through fights with other mice and an encounter with an owl
And her second set of siblings (tongue twister 2) gets devoured by a ferret.

But seriously, it is a cute little book despite these events.