Joe Simpson: We're Counting the Days Until Ashlee Gives Birth

With singer Ashlee Simpson-Wentzdue any day with her first child, the entire Simpson clan can hardly contain themselves -- except for grandpa-to-be Joe Simpson! Although Papa Joe -- as he hopes to be called -- is "excited," the 50-year-old can't help but laugh that he is "too young to be a grandpa!"

In addition to dealing with his own nerves, Joe shares that as manager of both his girls' careers, he has also been forced to convince older daughter Jessica Simpson-- who is thrilled to be an aunt-- to continue her touring schedule and perform at her remaining venues. "I'm trying to keep her out there until the baby's born. I have a couple of other dates I need her to play!"

Despite any doubts that Ashlee would have trouble taking on the responsibility of a baby, Joe reports that since finding out she was expecting with husband Pete Wentz, his 24-year-old daughter has "become a woman." Admitting that as a father "it's a transformation you never expect -- you pray for it, but never expect it," Joe shares that the doting couple have focused all of their energy in preparing for the family's newest addition. While Ashlee is "concerned about what she eats and how she prepares for the child," the newlyweds are also making sure the nursery is "green enough." Of his rocker son-in-law Joe says,

"Pete is the kingof details, so he wants to make sure the baby's room is just right -- the right colors, the right sheets, the right look. He's a great parent."

Although Pete recently said that the couple were waiting to meet the baby before deciding on a name, Joe jokes that he can confirm that the new baby will not be named after him! "I'm not allowed to give any hints, [but] I can tell you it's not Joe. I wished, I tried, but it didn't work."

Source: PEOPLE