Mildred Patricia Baena, known as Patty, reportedly worked in the family home as a housekeeper and assistant for more than 20 years, until January.
Amid the speculation, Schwarzenegger's wife and mother to four of his children, Maria Shriver, was in Chicago Tuesday at the star-studded tribute to Oprah Winfrey, which also featured appearances from Tom Hanks, Tom Cruise, Madonna, and ABC News' Diane Sawyer.
The former first lady of California paid tribute to Winfrey despite her recent marital troubles.
"For more than 30 years you have bestowed upon me the most amazing friendship. You have shown love, support, wisdom, and most of all, the truth …," Shriver said, pausing for a moment after she uttered the phrase "the truth."
According to the New York Times, there was a period 14 years ago when Baena was working at the couple's Brentwood mansion while pregnant with Schwarzenegger's child ... at the same time Shriver was also pregnant with Schwarzenegger's son.
Earlier today, two of Shriver and Schwarzenegger's children took to the Internet with reaction to their dad's admission that he fathered a child with one of their household staff members and hid the secret for years, shattering their 25-year marriage.
"I love my family till death do us apart," Patrick Arnold Schwarzenegger, 17, tweeted.
He also quoted lyrics to a song by hip-hop group Fort Minor that read: "Some days you feel like s*** … some days you want to quit and just be normal for a bit."
Pointedly, he recently changed his Twitter name to Patrick Shriver.
His older sister Katherine Eunice Schwarzenegger, 21, also tweeted (as KSchwarzenegger): "This is definitely not easy but I appreciate your love and support as i begin to heal and move forward in life. I will always love my family!"
They are two of the four kids that Shriver and Schwarzenegger have together.
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