Those in heaven may well be praying with us and for us, but that still does not give us license to violate God’s prohibition against communicating with or contacting those who have passed on from this earthly life.
We don't do anything forbidden by God, like try to conjure their presence or do seances or any such occult practice. We do acknowledge that, as fellow members of the Body, we love them and are loved by them--- in Christ --- and as sharers in the supernatural Life, we need them.
And how not? As we gave been taught:
We need this mutual spiritual assistance Christ has given us with all the members of the Communion of Saints.1 Cor 12:14-26
The body is not made up of one part but of many.
Now if the foot should say,
“Because I am not a hand, I do not belong to the body,”
it would not for that reason stop being part of the body.
And if the ear should say,
“Because I am not an eye, I do not belong to the body,”
it would not for that reason stop being part of the body.
... But in fact God has placed the parts in the body, every one of them,
just as he wanted them to be.
The eye cannot say to the hand,
“I don’t need you!”
And the head cannot say to the feet,
“I don’t need you!”