Well, I guess every member of the big cat club will weigh in on this topic! My momcat weighs eight pounds. She's the only slim one of the bunch. She gave birth to one who just got her annual check up and tipped the scales at 9 lbs. Not too large but larger than average, and she's got a small frame and was the runt. Her sister weighed 10 1/2 last time she went to the vet, but on the bathroom scales last month she managed to make the needle go to 12. The real porker is the boy, 20 lbs. But like Trevor, he is a large cat with a head the size of a grapefruit!!