Yes. A 7 month old kitten is absolutely old enough to be in heat. Is she also super affectionate and looking for attention more than usual? I had one that went into heat before I took her to the vet to be spayed. It was a long time ago but I would have to say she was about 6 months old. Walking around with her back end up in the air, meowing constantly. It's a good enough reson for me to spay my girls, even indoor cats with no males around. My vet says 5 months or 5 pounds and they can spay while in heat if you need to. Like if she's driving you crazy or if you have a male and need to prevent a pregnancy from happening.
***Edited By: MaxandAllie on 1/17/2008 8:49:33 PM*** Reason: sp