And sadly, he died before he got to the vet. We're devastated, and burying him yesterday was really tough on DC's 1 & 2, who're old enough to realise and understand - 3 & 4 are ASD and 5 and 3, so thankfully they've been spared any loss.
His sister-cat is naturally missing him, searching everywhere for him periodically, leaving him food, miaowing for him, and looking worried.
However we're now worried about how long we ought to/can leave it before we get another one. DH says a kitten might be easier to integrate, as Thulu-GirlCat might mother it, and that we should do it in a couple of weeks, so she's had time to adjust to Thulu-Boycat's departure, but not had long enough to get lonely or get used to being solo-cat.
I've no bloody idea, as they were/are my first family cats. Any advice? I don't want to do it too early, but I don't want to leave it too long, either.