Republican U.S. Senator Robert Portman, one time opponent against gay marriage, told CNN news correspondent Dana Bash Thursday that he now supports the institution after learning that his son is gay. 

"My son came to Jane, my wife and I, told us that he was gay and that it was not a choice. And...that's just part of who he is and he'd been that way as long as he can remember."

In 1996, Portman co-sponsored the Defense of Marriage Act, the law that defined marriage as between a man and a woman and denied federal benefits to same sex couples. In 1999, he voted against the right of Washington, DC same sex couples to adopt children, reported CBS news.

When son Will (21), freshman at Yale University at the time came out to his father, the report continued, Portman reassessed his beliefs, consulted his pastor, as well as, former Vice President Dick Cheney- whose daughter is an openly lesbian advocate for same sex marriage.  

"I think this is something that we should allow people to do, to get married and to have the joy and the stability of marriage that I've had for over 26 years. I want all 3 of my kids to have it, including our son," the Ohio senator said to CNN. 

Portman's announcement comes just days before the Supreme Court hears arguments on the Defense Of Marriage Act, an opportunity for him to speak in regards to his reversal.