How do stop my little dog from biting other dogs when playing?

I’d advise you to take that biting very seriously. It doesn’t matter that she’s little, or that she usually gets along with others.Seriously, all your little dog needs to do is injure the wrong being (human, dog or other) once and Animal control can be called out to assess the temperament, impose a quarantine, and possibly result in the early euthanization of your little dog’s life. If your dog has been exhibiting this in the house, it’s not a far stretch to say that without changing the behavior your dog may become a menace in the neighborhood, attacking other dogs or humans during walks or if you were ever to have a sitter watch or walk.

Look for a trainer who offers positive reinforcement training techniques. I’d suggest that you can interview people if you’re going to have a trainer and let them know that there is this one behavior that you need to fix first most importantly and make sure that they are confident when they tell you that they can help you fix it, which will require training sessions and reinforcement homework/ at home sessions daily in between. You can also look up positive reinforcement videos on YouTube. One renowned trainer of England, who had success with training tough cases is Victoria Stillwell

Biting during play is a common behaviour in many dogs, especially puppies. However, it's important to teach your dog to play appropriately to prevent any accidents or injuries to other dogs. Here are some tips to help you stop your little dog from biting other dogs when playing:

Socialization: Ensure your dog is well socialized with other dogs; this will help them learn proper dog-to-dog communication and reduce the chances of aggressive play behaviour.

Supervision: Always supervise your dog when playing with other dogs, and be ready to intervene if necessary. Interrupt playtime if you notice any signs of aggression or excessive biting.

Training: Teach your dog the "leave it" command so that you can redirect their attention when they get too rough or aggressive during play. Practice the command with your dog on a leash and offer positive reinforcement when they obey.

Consistency: Be consistent with your training and make sure everyone who interacts with your dog follows the same rules. It will help reinforce good behaviour and prevent confusion. Playtime management: Manage playtime with other dogs by selecting appropriate playmates, ensuring play is supervised and limiting the duration of play to prevent over-excitement or exhaustion.

If your dog's biting behaviour persists despite your efforts, consider consulting with a professional dog trainer or behaviourist for additional guidance.

This sounds like resource guarding, with both toys and possibly you as her people. If you google resource guarding you'll see lots of information about it. But I would recommend taking it very seriously, and anytime she growls/snaps at/or attacks another dog in the home she gets removed from the situation and isn't allowed to participate anymore. So for instance, if she's on your lap and another dog walks up and she growls or snaps at them then you immediately put her on the ground and don't let her back up with you. I think it's a great idea to just keep her separate if you're playing with the other dogs to remove her and them from the stress she feels.