My friends and I used to date white girls when I was a teenager, but now milf and step mother couples are quite common. Milf is a thirty-something year old step daughter of my best friend's mom, and my wife's younger half sister. Stepdaughter is my young niece. We have been married almost ten years and my wife's fondness for milf started as a teenager. My younger half sister feels jealous at times, and when we do go out she thinks her mommy has more power than she does!.