Let the kids and pet interact slowly with their own pace. Make sure to not force the interaction, it may leave both of them irritated. Let the pet observe the kids from a safe distance to build trust.
Teach the kids how to gently pet the animals. Explain them that pulling tails or fur can upset the pet.
Make sure that you supervise the playtime and ensure safety. This may result in no signs of stress or discomfort in the kid or pet.
Explain kids that even pets have their personal space which they don't like being disturbed. Teach them not to disturb the pets especially during sleeping and eating.
Explain the kids animal language like growls, tail wagging, or purring. This will help them understand the pets better and be familiar with their emotions.
Building relationships always takes time. Allow your kids and pets to spend time together for building trust and creating a bond.
Set some rules for you kids. Teach them to not tease or hit the pet. Also, make sure that they don't feed the pet without your permission.
Teach your kids that even pets have their needs. Assign them with easy tasks to make them understand about their needs. Teach them to groom them, take them on walks with you, fill their water bowl, etc.
Start training your pet with simple commands like sit or stay and involve your kids as well. This will ensure a good bond and help build obedience.