<P> With sisters Kim and Khloé, Kourtney is involved in the retail and fashion industries . They have launched several clothing collections and fragrances, and additionally released the book Kardashian Konfidential in 2010 . </P> <P> Kourtney and her siblings are popular on social media from which they derive most of their revenue by endorsing products such as waist slimming pants, beauty products, Coca - Cola and prescription drugs, for which they are paid (as of 2016) between $75,000 and $300,000 per post on Instagram, Facebook and Twitter, as per CBC Marketplace . </P> <P> Kourtney Mary Kardashian was born in Los Angeles, California on April 18, 1979 to Robert and Kris . She has two younger sisters, Kim and Khloé, and a younger brother, Robert (Rob). In 1991, her parents got divorced and her mother married Bruce Jenner, a 1976 Summer Olympics decathlon winner (Jenner later changed her name to Caitlyn) in 1991 . Through their marriage, Kardashian gained stepbrothers Burton "Burt", Brandon, and Brody; stepsister Casey; and half - sisters Kendall and Kylie . </P> <P> She attended Marymount High School, a Roman Catholic all - girls school in Los Angeles . Following graduation, she moved to Dallas, Texas, to attend Southern Methodist University for two years . Kourtney then lived in Tucson, Arizona, where she graduated from the University of Arizona with a bachelor's degree in Theatre Arts and a minor in Spanish . Her classmates included Nicole Richie and Luke Walton . In 1994, her father garnered public attention as an additional defense lawyer for football player O.J. Simpson during his murder trial . </P>

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