I have a hard time understanding how people so misunderstand the Church’s doctrine of the communion of saints, unless they have deeply ingrained Protestant errors.
If your children were sick, would you pray for them? If your answer is no, I have nothing else to say. If yes, then why? They don’t need your prayers; they can go directly to God themselves, can’t they?
This is what Catholics do; we pray for each other, and we ask others to pray for us. This is not optional because we are all united by baptism, including all those on earth, purgatory, and heaven. If you believe God hears and answers the prayers of people like you and me, how much more will he hear the prayers of those in heaven who have already been perfected? Mary, the virgin mother of God, is first among all the saints, but is much more like her fellow human beings than she is her son, who is, was and always will be a divine being.
We know from scripture that Jesus was obedient to his mother when he was 12 and was found teaching in the temple. He consented to her mere suggestion at the wedding in Cana. If you reject the communion of saints, you have already separated yourself from the Church, but just like the prodigal son, the father greatly desires that you return.