I also have dead relatives including dead father, mother, in-laws, and spouse. Dead friends too.
Catholics don’t “try to contact their dearly departed” in the sense of calling them up with a crystal ball or Ouija board or asking them to appear in the room. This is considered conjuring up the dead and it is forbidden by the Church because, as someone else said, it is likely to open up a portal to the demonic and get some demon on the line rather than your dear departed Dad.
Not only is such “conjuring up” forbidden by the church, it’s completely unnecessary. If you want to talk to a deceased person who you have reason to think is in Heaven, whether it’s a saint of the Church or your dear departed Dad, just talk to them. If God wills them to get your message, they will get it. Don’t forget also to pray for your deceased loved one’s soul in case they are not yet in Heaven but are still in Purgatory.
I talk to my dead loved ones, and many saints, all the time. I don’t need or use a crystal ball or other “magic” and I don’t try to command them to appear in my living room. I just converse with them and ask them for help (the “help” is understood that they pray to God for me or otherwise go through God with any communication, in other words, God is controlling this and it’s all according to God’s will). This is not considered calling up the dead, and it’s totally normal. So if your question is can you just talk to your deceased Dad (or other deceased relative or friend), without any occult stuff involved, the answer is Yes. Don’t expect to get an answer back though. God might permit you to get one but you should never expect or demand one.
