Arnold Schwarzenegger's life began to unravel when he realized he had another child -- and it wasn't with his then wife Maria Shriver.

Schwarzenegger and his longtime housekeeper Mildred Baena had an affair and he fathered their son Joseph. However, it took him seven or eight years to realized Joseph was his. 

It wasn't until Joseph "started looking like me, that's when I kind of got it. I put things together," the action star and former California governor, 65, told 60 Minutes on Sept. 30, according to People magazine

In the meantime, Baena continued to work for the family while Schwarzenegger clandestinely provided her with financial support.

Schwarzenegger admitted that he "lied" to Shriver, his wife of 25-years until he was no longer governor of California. He also kept his secret hidden from his four children with Shriver. 

"It was very difficult, strange, bizarre," Schwarzenegger said. "I just said to myself, 'Okay, I'm going to put this away.'"

During his CBS interview to promote his book, "Total Recall: My Unbelievably True Life Story," Schwarzenegger said he revealed everything to Shriver during a marriage counseling session. Shriver filed for divorce not long after. 

"I asked them for forgiveness," he said of his five children. "They cried. It tears your heart out." 

Schwarzenegger claimed he did not show the book to Shriver before it went to print. He also refused to speak about his son Joseph.

"The important thing that everyone should know is that I take care of him and I take care of her [Baena]. And I fulfill my responsibility and I'm glad to do that." 

The actor reflected on his choices and admitted, he made a huge mis-step. 

"If you would have asked me 10 years ago, five years ago, two years ago, what is the most important thing in my life, I would tell you over and over, it's my marriage, it's my family. So the thing that really meant the most to me kind of fell apart because of my doing. That is something that I will always look back and say, 'How could you have done that.' "