Many Biblical scholars agree that Christ's words meant that we cannot talk to the dead.
You can’t talk to dead family members. You will really be talking to demons who pose as them.
12. Luke 16:25-26 “But Abraham said to him, ‘Son, remember that during your lifetime you had everything you wanted, and Lazarus had nothing. So now he is here being comforted and you are in anguish. And besides, there is a great chasm separating us, and anyone wanting to come to you from here is stopped at its edge; and no one over there can cross to us.’
13. Hebrews 9:27-28 And just as it is destined that men die only once, and after that comes judgment, so also Christ died only once as an offering for the sins of many people; and he will come again, but not to deal again with our sins. This time he will come bringing salvation to all those who are eagerly and patiently waiting for him.
I agree with the doctrine *in general* but disagree that the parable of the Rich Man and Lazarus is the source for it.