Lulu and the Hamster in the Night (6)

Lulu adopts a hamster, but she can't tell Nan about it because Nan doesn't care for most animals--especially not hamsters. It's her birthday this weekend and Lulu and Mellie are staying the night. Lulu doesn't want to leave her new hamster behind, but can she and Mellie keep it a secret from Nan over the weekend?