My cat did it too. Luckily, we had 2 boxes at the time. He was only able to get the lid off one, he couldn't fit through the door to the second box, and all the chicks hightailed it to the other box. I think he also hadn't quite figured out what to do with them. I'm pretty sure they would've been lunch if he'd been with them much longer. He's always hanging out by the bathroom door, saying "Mommy! I want to see the peeping things!"