The former Beatle remains one of the most notable "househusbands" — as he called himself — of all time. Lennon had two sons, Julian (with first wife Cynthia, born in 1963) and Sean (with Yoko Ono, born on John's birthday, October 9, in 1975). The musician had missed out on most of his first son's childhood, and was determined to be a better dad to Sean.
In the introduction of her book "Real Love: Drawings for Sean," Ono wrote of her pregnancy with Sean, "John was ecstatic. 'I'm going to raise this baby, Yoko. You do the business,' he said. It was that simple."