StedmanOO has asked all the right questions and to be honest there's really little wiggle room for a definitive answer without knowing more.
If you are not the coach or the family involved you have no dog in the fight except you are unhappy with the atmosphere with the team. If this is the case, I suggest a private meeting without the kids. You and the coach or their staff if that's how they want it. Express your concerns. If they don't have any answers your personal choice would be to leave the team. You can only control your own destiny here. Perhaps the coach and staff are unaware of the friction but I really doubt that. lol. My guess is they are trying to figure out what they should do to resolve things.
Before you make it an "Us or them" situation, discuss with your daughter what she wants to do. If she's not seeing it and the ones struggling with things are you and your family, perhaps you could tolerate it by putting distance between you and the offensive family. My guess is if you are experiencing difficulties, others will be willing to join you. I suggest you still have the private meeting with the coach so they understand you're trying to be the bigger person for the sake of your child. An entire summer of misery is not what you signed up for but be sure you are ready to follow thru with things in the event you have to choose.
If your only concern is you are empathizing with the coach and staff, your private meeting to express your support I'm sure will be appreciated. I hope it works out.