Though Holly Madison has had to share her octogenarian boyfriend, Hugh Hefner, with the two other Girls Next Door, Bridget Marquardt and Kendra Wilkinson, it wasn't the lack of monogamy that ended their relationship. Nope, it was babies. The couple tried to get pregnant earlier in the year, but the relationship took a turn for the worse when it looked like there weren't going to be any little bunnies running around the mansion. "With my sperm count, it's not possible," Hef explained. "I was willing but it was not possible…She'd like to be married and have children, but it's not in the cards here for me." Of course, Hef has already begun his search for new girlfriends.