Childs play

Why do children automatically cling to the person they know will give them their way everytime? It bugs the hell out of me when my daughter will want to be with a certain person because of what they let her get away with! I honestly feel like I need to start putting adults in check if they want to be around my kids. I know that this is going to continue through her whole life but seriously people if I put a rule down it sticks, if I'm around or not! I don't think it helps that I'm already tired and irritated from being pregnant, which I honestly try to control. But cut me some slack here, I need a little back-up. I guess this is the start of when your children rebel against you. It's sad can't she just go back to 2 years old!?