The family tree lists Patricia's birth as 1950. But in "Witchstock"(6:11) Grams' husband Allen/Jack says he took "the baby" to his sister's. The "baby" would have been either 14 or 17 years old when her father died depending on which version you accept (1964 family tree, or 1967 the real Summer of Love in S.F.). And Penny, according to the family tree, would have been 13 years old when she gave birth to the girls' mother Patricia.
'Leo states that he and Piper are former lovers from in and around the roaring '20s. It is also established that "Leo" died during World War II. Leo was in his twenties when he died in World War II so the "Leo" incarnation of his soul would have already been born in the 20s, thus he could not have been Piper's lover at that time as Leo was already alive as a young boy. Both incarnations could not be alive at the same time.' However, Leo's past life would have had to have died sometime between Feb. 17, 1924 and May 6, 1924 when present Leo was born. This could easily have happened.
The date of birth given for Phoebe in episode does not work out with the time lines in "That '70's Episode" and "Forever Charmed".
The family tree indicated that Penelope Johnson (Grams) died in 1968. The girls got their powers when she died in 1998, hence the beginning of the series.
When Phoebe pulls out the family tree and finds P. Russell, the dates are July 2, 1894- Feb. 17, 1924. She then states that the dates match up, as well as the age. This would make Phoebe 30 years old, which we know she is not. When she first finds her name, the date of birth is November 2, 1975. This makes Phoebe 24 at the time of the episode.
Leo has already said he follows modern baseball in "The Devil's Music" when he knew the details of Dan's career-ending injury. It seems odd that he can't think of a single modern baseball player to name when Dan asks for his favorite. It also seems odd he'd name an old one like Joe Dimaggio, considering White Lighters are supposed to blend in (according to when he's first found out), so he should be better at hiding his age.