Threesome Forcing a Step Mom To Teach Teenagers About Love, Sex and Dating - "Foursome with Step Mothers" byondaowerbell This video will teach step moms how to encourage their teens to have a foursome. The step moms in this video are real people who were once single and now married with children of their own. They all agree that forcing a teen into a foursome is not a good way to go. The video discusses the foursome and the pros and cons of having foursomes as well as some ideas on how to make it work for your teen and your family..