Is it fair?

My husbands sister invited only my 3 year old to go to the movies with her and her older teenage daughter to the movies but didn’t invite my 10 year old do you think it’s fair? I know my 10 year old will feel left out to me it’s not fair they only invited her only. Or am I just overreacting she has always favored only my 3 year old and don’t care much for my 1 year old or 10 year old smh. I don’t even know why she would wanna take a 3 year old to the movies my daughter will not stay sitting down the whole movie but whatever It’d make more sense to take my older child who’s well behaved.