The family tree says that the name of Grams's first husband (Patty's father) was Jack Halliwell, but in the season 6 episode Witchstock, his name was Allen Halliwell. According to Witchstock he died in 1967, not 1964 as the family tree says. Also, Grams couldn't have died in 1968 as the family tree says. After Patty dies, Grams raises Prue, Piper, and Phoebe. Grams dies about six months before the season 1 episode Something Wicca This Way Comes. Her year of death should read 1998, not 1968.