Thank you for reaching out for help. When a small child needs to learn what to do when they feel angry, frustrated, sad, or disappointed, parents must teach them. We recommend that for any teaching you do with her, you "show and tell" what you want her to do. Here are some tips:
Do your teaching at a neutral time, not in the heat of the moment. Let her know that you get mad, too, but you can't hit, bite, pinch, or scream at people, and neither can she. Suggest that instead of her doing those things, she should try something different:
- Go get her favorite stuffed animal or blanket and hug it really, really hard.
- Put her "handcuffs" on (hands behind her back with thumb and pointer finger locked around the wrist of the other hand).
- Make the meanest face possible and say in a gruff voice, "I'm MAD!"
- Immediately go tell an adult about the problem and ask for their help when someone else took what she wanted or wouldn't share.
Give your daughter positive reinforcement for practicing, and practice with her frequently throughout the day, every day. Keep each practice brief, and make it fun.
You are your daughter's first and most important teacher. Teach her what she needs to know in future situations, teach her better ways to handle herself the next time she feels upset, and practice those skills in advance so she knows what to do the next time she becomes upset.
As far as the other children at daycare, you can't control how other parents are raising their children, but hopefully the daycare staff is consistent in their discipline practices and addressing the behaviors in line with your parenting strategies. It might be a good idea to sit down with the daycare staff and other parents to ensure that everyone is on the same page.