I have two cats about six years old. My male cat has always been very active and has never weighed more than 10 lbs, usually ranging b/t 9 and 9.5lbs. His sister is also at a healthy weight around 10 to 10.5 lbs, but is an absolute food gremlin and less active. As a result I’ve skewed their feeding routine towards keeping her more lean, since the vet said my male cat‘s weight is healthy. However he’s 8.8 lbs now - the first time dipped below 9 lbs since he’s been a kitten and is looking leaner than I would like. He’s still healthy and acting normal but I don’t want him to lose any more.

Looking for recommendations for high quality/healthy but calorie dense treats I can sneak him on side to get his weight back up, and maybe some lean treats I can give his sister when she inevitably sniffs out his extra snacks and starts yowling her head off.