Joseph Baena, 18, donned a blue cap and gown during the ceremony at Frontier High School in Bakersfield, California on Thursday (28May15), but his famous father was not present to witness the milestone event.

The Terminator star stunned Hollywood in 2011 when he confessed to fathering a lovechild with his former maid, Mildred Baena, during his marriage to Maria Shriver.

The explosive revelation prompted the breakdown of the couple's relationship, but Schwarzenegger promised to treat Joseph "as a son" and "take care of him financially".