In laws asking for favors when they don’t talk to me

So my SIL hasn’t spoken directly to me since May last year. She called my husband to ask if i would be willing to help transport her son from A to B.

Soooo she lives in a different state than the child’s father. He used to take planes but I’m not sure why he stopped, maybe due to the developed fear since she talked to him about all the plane crashes happening. Anyways his father picked him up from my SIL home and now wants to send him on a plane vs driving the 12-15 hours. She claims that the father spoke to him but think he’s only agreeing because he’s too scared to tell him no. So now she has to get him back but wants me to drive him 4 hours away.

I feel for the kid. If he’s truly scared I don’t want to traumatize him. Especially since he’ll be alone with the exception of a flight attendant if he were to go on a plane.

My relationship with the child is not strong. It was in his early years but we moved away after a lot of disagreements and other serious issues between my family and my SIL family. She has no one else here to help her out. My husband has to work so it’s me or no one. I don’t know if she would be forced to drive all the way or if she would force her kid on the plane too. Part of me wants to help. I want to be involved but my SIL in just a lot… the other part is annoyed that she’s reaching out just for help and now I have to take my toddler on a long drive there and back home…on my day off… on a school night and I’m pregnant. Maybe I’m being selfish. I guess I want your opinion what would you do. I feel if I say no it will also cause issues with my MIL and FIL I’m just starting to build a healthier relationship with them and don’t want to damage that either. My SIL will probably still not talk to me. Not that she should have to. Just trying to be helpful and it would be nice for her to try at the relationship as I used to. I’m considering agreeing to it with no expectations but maybe I should just say no. It is her problem…if it was my kid I would be going to get him.