Hi! I have a boy and girl both indoor cats, brother and sister from the same litter and they're coming up to 2 years old, both neutered. They get on really well and both bonded with me really well too, particularly the boy who follows me around and likes to be close to me.
My question is, when she decides (rarely) she wants a fuss he will often come close but not join in the fuss, but he always then puts his nose under her tail and will continue to sniff her for about a minute or so even after she has moved away (which she does as soon as he arrives). I'm assuming he's jealous, but it seems a strange behaviour, can anyone explain?