Don Lothario is such a weasel My ambitious general practitioner, Valerie (we call her Dr. Woohoo around here) has three lovers, and got preggers by Don Lothario, and so she invited him to live with her (while still engaged to an older man in the neighborhood). Of course, Don, a lout with few skills, sits around playing chess and making grilled-cheese sandwiches all day. Just before the baby arrived, he invited his three other lovers over for a hot tub party, and so Valerie invited her two others over for the same, and after several hours of poking, slapping, crying, grossing out and so on, the little darling was born and everyone else finally went home. Now Don pulls that whiny little frown of his whenever it's his turn to change the diaper - one of his constant fears! So there goes his mood meter. Tough!
Poor baby. Romance sims are unpredictable that way. I've had some that were very good parents and some with that constant "change diaper" fear. I guess it depends on their personality.