Tammy Knickerbocker, joined the cast as a 46-year-old single mother of three in Season 2 at the recommendation of her close friend of over 15 years and then-housewife Jeana Keough. Knickerbocker's family includes her two daughters from her first marriage, Megan and Lindsey, as well as a young son named Ryley from a recently ended relationship. Her first marriage to Lou (who died of a heart attack at age 67 on April 24, 2007) ended when he had an affair with his assistant and their lucrative business went bankrupt. Her lifestyle has been "reduced" from being married and owning one of the largest houses in Coto de Caza to being single and renting a $1.3 million house in the community while her permanent Coto home undergoes renovations because of severe water damage.
Another twist to her storyline is that Ryley's father, Duff, works in Coto as Gunvalson's home office manager. Knickerbocker and Duff attempt to balance their "friends with benefits" relationship with raising their young son. In the end, however, Duff and Knickerbocker decide to end any romantic relationship. Duff swears off the "crazy women of Coto de Caucasian" and Knickerbocker introduces the new man in her life to the other Housewives at Gunvalson's splashy end-of-summer barbecue party.
Although Knickerbocker left the series at the end of Season 3, she makes a cameo appearance at the end of Season 4, when she attended a party with current and selected former housewives, and another appearance for a Bunco party hosted by Tamra Barney.
Tammy currently lives in Coto de Caza, California