Halloween is a family holiday??? Halloween for older kids is specifically about going trick or treating with friends. Were you going to make her go with your 6 yr old and her friends? I completely agree with the 11 yr old.

OP this says a lot about you. Unless she was being punished there's no reason to keep her from going and the fact you suggest she minipulated him makes me think you have jealousy issues. It's not a family holiday it's a friend holiday and as a child it was a night out without parents after dark holiday. You were wrong.

Did you promise your 6 yr old that she was going to go with him and you knew he would be upset?

Next year, you need if she is with you on Halloween, ask her in advance what her plans are and you also need to make plans for your DS to go with his friends.

Husband realized he was wrong and silly then backed down. Not the same as backing down after a temper tantrum about doing the dishes or flying to grandmas for Christmas. Excessive rigidity to prove a point is bad parenting.

Also. Is Halloween really a holiday.