Arnold Schwarzenegger spent quality time with his 13-year-old son, Christopher, for Father's Day.

PHOTOS: Arnold Schwarzenegger Has Lunch with his Son on Father's Day

The two were spotted having lunch at Marmalade Cafe in Malibu, Calif. on Sunday afternoon.

Arnold and his wife of 25 years, Maria Shriver, separated last month and it was revealed that he fathered another 13-year-old son with the family's housekeeper, Mildred Baena.

Shriver spent Friday night at the U2 concert in Anaheim where Bono dedicated a song to the former First Lady of California.

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