S.M.
A good start would be to let the dogs or other kids play with her in a "controlled environment". With the dogs have her play with them and get used to them. Once she understands that they only want her food and not her toys she will be more understanding. My 2 year old did this for a while with one of our dogs who follows her everywhere in the off chance that she may drop a snack. If it hits the floor the dogs can have it, but if they take it out of her hand they get in trouble. We did this as well with her and my neice (4 yrs old). My neice would always take toys away from my daughter because she was bigger and she could. This made my 2 yr old very afraid to play with anyone, even her 5 year old brother. We had some neighbod kids over that were older and that understood the situation (6 and 7 year olds). After playing with them for a week or so she started to trust again and understand that she had to share her toys when other kids were around, but that when they left she got them al to herself. We still fight a bit with her and my neice but they are getting better about it. The best advice to give is to let her know that you are behind her 100% and that if the dog gets her snack you have more and that if someone takes her toy she will get it back later and that there are better things to play with. If not she may resort to violence like hitting or biting. My cousins little girl did that, she actually bit my daughter on the nose when ours picked up one of her toys. needless to say, our daughter became terified of her and biting in general and now that the biting has stopped (a year later) will she play with her 2nd cousin. It is tough but it can be overcome with lots of positive reinforcement.