In 1777, Bimperl died and the Mozarts bought a male dog, giving him the same name.
I found this information on the Mozart Forum.
Fox Terrier. Image from Wikipedia.
Write me, how is Mr. Canary? Does he still sing? Does he still pipe? Do you know why I am thinking of the canary? Because there is one in our anteroom that makes the same little sounds as ours.
How is Miss Bimbes? Please present all manner of compliments to her.
As the weather is fine, [Nannerl and I] take an early walk every day with our faithful Bimperl, who is in splendid trim and only becomes very sad and obviously most anxious when we are both out of the house, for then she thinks that because she has lost you two, she is now going to lose us as well. So when we went to the ball and she saw us masked, she refused to leave Mitzerl, and, when we got home, she was so overjoyed that I thought she would choke. Moreover, when we were out, she would not stay on her bed in the room, but remained lying on the ground outside the porter's door. She would not sleep, but kept on moaning, wondering, I suppose, whether we should ever return.
Give Pimperl a pinch of Spanish snuff, a good wine-biscuit, and three busses (kisses).. . .
Now as to my mode of life: As soon as you were gone I played two games of billiards with Herr von Mozart who wrote the opera for Schickaneder's theatre (The Magic Flute); then I sold my nag for fourteen ducats; then I had Joseph call my primus (valet) and bring a black coffee, to which I smoked a glorious pipe of tobacco...Since his health was failing, Mozart's doctor advised him to buy a horse and ride every day. However, Mozart didn't care for the exercise and sold his horse.