She was something of a silly creature. Little black strawberry nose, little black lips. A curious under bite, perhaps normal for a shitzu. But she was a great dog.

Donna rescued her from a breeder who had worked her too hard. She nursed her after spinal surgery when she had fallen off the bed, took her for long morning walks along the canal, carried her down the stairs when they became too steep for her. If you loved Donna, you loved Sissi.

I thought I was a dedicated cat person, and often chaffed against the structure and uncompromising affection of the dog. But Sissi was relentless. She wanted to be where we were, and she wanted to play: not Frisbee (unfortunately), and even the cat could fetch better, but rolling around on the floor, nipping and grunting, full of life, full of dog.

She loved going for a drive. Once during a walk she took off down the street and jumped into someone else's car through an open door. Her adventure lasted only a few minutes before she was rescued, quite reluctantly.

We let her chase chickens, but only once. She chased squirrels more than that, but didn't know what to do with them when she got close. She wrestled with the cat, with whom she had numerous cross-species misunderstandings. She snored on our beds, she wanted chicken from the table, and we all watched "Six Feet Under" together.

And then she was fifteen. As sometimes happens, her age crept up on us until she couldn't find a comfortable way to sleep, and our play with her was infrequent and laboured. We had a good walk with her last night, her last as it turned out. It was like the old Sissi was back for a few moments, and she nearly pranced and led the way, as she had done so many times before. But she paid for it today. There was blood on her face this morning, and she vomited something black after I went to work. Donna called me crying. When there is no good time for something, sooner is better.

I stroked her chest and felt her heartbeat, and then it faded away, but Sissi is still strong in us, strong with her dog love, which must be the purest love of all.