Oh they can definitely hear us, and it's amazing how they respond~! I remember my brother and I discussing my grandfather over the phone years ago when my lights went out and my door slammed shut. I was so scared at the time I ran out the door when I found it, lol. I called my brother back and told him what happened; he experienced some strange activity, too. My grandfather played video games on his SNES gaming console, and he loved Donkey Kong Country. My brother had been playing Donkey Kong Country one night in the living room, and got up to take a break. In the living room, he heard the volume on the television go up full blast. Everybody else was in bed, so nobody else could have done it, and that wasn't something that t.v. did.
But yeah, I think that was your father-in-law too. I wonder how many times though, if any, that I have missed signs and communication attempts from those who have crossed over. I try to keep my eyes and ears open at all times.