S.G.
Your daughter is acting normally for her age believe it or not. She doesn't cry at all loud noises because she knows those noises. She knows if you or your husband does something loud, she is ok, she is safe. She knows that at daycare the kids there make loud noises and she is ok still. Then a new kid comes in and starts making loud noises non stop by the sounds of it. Suddenly things changed and she doesn't know that his making loud noises aren't going to hurt her and that she will be ok. It is a new and unsure situation. This little boy might like having the control of making her scream also so the situation should be watched. When she starts crying, it would help if the day care provider would hold her and tell her that the noise is just noise. Then teach the kids "inside voices" because even a 2 year old can understand that. It is better for all the childrens ears if they understand that inside voices don't scream. It won't take long and she will be more comfortable around this young man even if she never likes or trusts him.