Tell your kid that the pet will be around soon
It often helps to tell your kid that the pet, which has just died, is not going anywhere and it will be back soon. If your kid has lost a pet that lived with him for months, you can console the kid by telling him that the pet has gone to take some rest and will come again after a few days. Hopefully the kid will soon get over the death and his life will be back to normal.
Draw a picture of pet
Little kids can be calmed if you draw them a picture of their pet and tell them that your pet has taken a new form. The technique may not work with the older kids though. Kids are attracted to things that they find interesting, and if the picture is good, they will surely pay attention to it and forget their loss.
Write a letter to their pet
You can ask the children to write a letter to their pet. Writing a letter will work wonders for the kid as they will be take interest. Tell them that the pet has gone for a break and they can write a letter to ask how everything is going.
Gather up photographs of their pet
Gathering up pictures of their pets and making an album can help you console your kids.
Get them involved in regular activities
It will help you calm the children if get them involved in regular activities like sports, going out for a bike ride, shopping, and other recreational activities.
Buy them new pets
If nothing works, you can buy them a new pet. This will surely work but if you can calm the children without telling them that you will get them a new pet, it is better. New pets will soon make them forget the loss of their old pet.