http://www.dailymail.co.uk/tvshowbiz/article-2578421/Arnold-Schwarzeneggers-love-child-Joseph-Baena-reveals-muscles-high-school-swimming-championships.htmlHis mother Mildred - who previously worked as Arnold's maid - produly posed with her son after the event.
Employed as Arnold's housekeeper for 20 years, Mildren had an affair with the Terminator star and became pregnant with Joseph.
The fling was kept hidden for years and Joseph was never told the identity of his biological father.
Arnold admitted paternity of the teen during a May 2011 media firestorm.
Birth records revealed Joseph was born just a week after Schwarzenegger's youngest son with Maria Shriver.
After 25 years of marriage, Arnold and Maria separated.
But despite filing for divorce in July 2011, Arnold and Maria have yet to finalize their split.
For his part, the former Governor of California has taken financial responsibility for the child as it was reported that he had bought a four-bedroom house, with a pool, in Bakersfield for Baena and their son in 2010.