Rep. Tulsi Gabbard’s father said the Hawaii congresswoman’s apology for her previous stance on homosexuality broke his heart.

Gabbard, who announced earlier this month she’s competing for the 2020 Democratic presidential nomination, apologized Thursday for her previous work for an anti-LGBT organization run by her father.

In a nearly four-minute video, Gabbard said her upbringing shaped her previously held views, because her father, Hawaii state Sen. Mike Gabbard, was an outspoken activist against gay marriage.

“I also grew up in a socially conservative household,” Gabbard said in the video, “where I was raised to believe that marriage should only be between a man and woman. … While many Americans may be able to relate to growing up in a conservative home, my story’s a little different, because my father was very outspoken. He was an activist who was fighting against gay rights and marriage equality in Hawaii. At that time, I forcefully defended him and his cause.”

Mike Gabbard, in an email exchange with the Washington Examiner, said he was caught off guard when he saw his daughter invoke his work against gay marriage in her apology.

“I’d always known that as a child, Tulsi had been deeply affected by the conflict between myself and the gay community. But after seeing her video the other day, what she said broke my heart. I never realized how much trauma I put her through because of my overly aggressive advocacy for traditional marriage,” he said in an email. “We continue to have a very close relationship, and do not allow our differences on this issue to interfere with that.”

Mike Gabbard has served in the Hawaii state Senate since 2006. Although a Democrat now, up until 2007, he was a member of the Republican Party.

Tulsi Gabbard has faced intense criticism for her previous work for the Alliance for Traditional Marriage, an anti-LGBT organization run by her father which opposed gay marriage and promoted conversion therapy. Mike Gabbard was also the director of Stop Promoting Homosexuality and served on the steering committees of the National Campaign to Protect Marriage and Save Traditional Marriage, according to CNN. He also hosted an anti-gay radio show called “Let’s Talk Straight Hawaii.”

Mike Gabbard said he still believes, as a socially conservative Catholic, that marriage should be between a man and a woman.

“I know that Tulsi’s position, although different than mine, comes from a place of aloha, respect and compassion for other people. So, although I disagree with her, I respect her position,” he said. “I have to admit that she has made me more empathetic and understanding of the difficulties that gays face in society.”

The congresswoman has dramatically shifted her views on the LGBT community since her teenage years working for her father and subsequent election to the Hawaii state legislature in the late 1990s and early 2000s. She was elected to serve in Congress in 2013 and has supported legislation to protect LGBT individuals.

Despite their differences on the issue, Mike Gabbard said he supports his daughter’s bid for the presidency.

“Even though I disagree with her on that one issue, she's intelligent, loves the American people, and will stand up to protect our environment and keep us out of stupid wars,” he said.