Did Patty Know Her Fate?

That 70's Episode is one of my all time favorites of Charmed.

I can't help noticing how the sisters hug their mom and tell her how they missed her. Later, Penny finds out inadvertently that she died in the late nineties. She says that their powers would only have been unbound if she died. The sisters look sad and she immediately gets what the future holds for her.

She goes on to say that the girls shouldn't say any more about the future. But really, if I was Patty, I would have suspected that I was also dead in the nineties. They hug her so much and act like they have not seen her in years (which they hadn't). When they are set to return to the future, they hug her again as if it was the last time they'd see her. Surely she must has suspected that she died young. Don't you think?