A short thread on animal mourning, prompted by observing our remaining dog, Calvin, over the last month. Calvin is seven - half the age of Hobbes, our late dog. He first started following us when he was a stray in Beijing when we took Hobbes (and another rescue foster) for walks

He was clearly drawn to the idea of having a pack - or a family, which are the same thing for dogs. Hobbes was very accepting of him, though he never stopped insisting on his place as First Dog, despite being considerably smaller.

For the last six and a half years, then, they were apart for, at most, a few hours at a time. When they flew from China to the US together they shared a cage. They often sat on top of each other on the sofa, and they play-wrestled a few times a day.

When Hobbes started going into decline this year, Calvin stopped play-wrestling with him even if Hobbes offered him an invitation, possibly because he was afraid of hurting him. But if we put food out or were about to go for a walk and Hobbes was asleep, Calvin would fetch him.

When Hobbes had a seizure and had to be rushed to the hospital, Calvin - who was left at home - was deeply distressed. When we came home without Hobbes several hours later, he vocalized strongly and ran around looking for Hobbes.

The next day, when we took him for his morning walk, he rushed downstairs and started searching. When we headed over to the hospital to say goodbye to Hobbes, he was also super-eager.

They spent a couple of hours together on Hobbes' last walk. Hobbes was very weak, and didn't express his usual excitement on seeing us, or Calvin, but they walked together and Calvin nuzzled him.

Calvin was with Christina when Hobbes died - only I and the vet were with Hobbes - but he wasn't distressed by leaving without him, nor did he look for him when he got home, or in the subsequent days. He knew that it was a goodbye, somehow.

But he's still been visibly affected since then. He is much clingier to us, and more distressed when either of us leaves the house. He's reluctant to go out with our regular dogwalker, who he loves, though he's ok when they get downstairs.

He still plays by himself, or with the cat, joyfully. Sometimes he checks out other small dogs on walks inquisitively. He loved raising our rescue puppy (who went to another friend). We will get him another friend.