It's heartbreaking to watch your other pet mourn a loss. Are they exhibiting signs of anxiety or nervousness? Is he or she running around whining or meowing looking for their pal? Is there a loss or decrease of appetite? Are they going to the bathroom more frequently than normal? These are just some of the symptoms to watch for.
Is there a cure? There really isn't one, as many animal lovers will confess. They truly never stop missing their pet. But it may help to introduce a new one into the family, but only when ready, and if you think your other pet(s) may be receptive. In the meantime, there are some things you can do to help cope with the loss. The most important is to set time aside each day to spend with your other pet(s). Try not to deviate from their regular schedule. Animals like routine. Play with them using their favorite toys, or introduce some new ones. Animals don’t understand when their buddy has suddenly disappeared. The biggest and most important thing you can do is be there for them, and love them. Your pets give you so much unconditional love, yet ask for so little in return.
Enjoy them, and they will give you and your family many moments of joy you will treasure forever.