I found him stretched out on his side on the top level of his cage, like he does when it's hot. Only thing weird was that he's normally bopping around in the morning waiting for breakfast. I thought for sure he had some kind of intestianl blockage (rabbits have sensitve digestive systoms). Good news is, all is well, and Mom's heart is working just fine. By the time I put Caleb in the pee pen and came back in, Shaker was up and looking to eat. I got up about a half hour earlier than normal, so I'm thinking maybe he was just waking up. Sometimes I swear these critters of ours are plotting against us!