HOUSTON (AP) — Beau Miller and Patrick Summers have been dating for four years, but last December was the first time they spent Christmas at Miller’s parents’ home.

It seemed like a breakthrough, since the younger Miller is an HIV-positive gay activist and his father Rick is a conservative Texas state lawmaker.

But barely seven weeks later, Rick Miller filed a bill that would repeal local ordinances banning discrimination against gay and transgender people, attempting to roll back rules passed in all of Texas’ largest cities.

“We were invited to Christmas, and I thought that was a good step,” said Beau Miller, a commercial litigation and product liability attorney who works on the 41st floor of a gleaming office tower in downtown Houston. But now, “My dad wants people to be able to have the opportunity to discriminate against his own son.”

Across the country, some conservative legislators have been trying to fight back against a series of new gay-tolerant policies even as other, national Republican leaders argue it’s time for the party to abandon the issue. Lawmakers struggled for weeks over gay-related measures in Arkansas and Indiana this spring.

A more personal side of such divides has already arisen in high-profile Republican families, including Ohio Sen. Rob Portman and his gay son and former Vice President Dick Cheney and his lesbian daughter. But nowhere is the human dimension now more vividly illustrated than with the Millers.

In March, the younger Miller went to the Capitol to confront his father over the proposal. They haven’t spoken since, except for exchanging text messages when each had recent birthdays.

At Christmas, Beau Miller and Summers, a professional musician, brought a gift of a high-end home fragrance and sat for an hour, chatting with his parents and grandparents, who are in their 90s.

“We talked like families do,” said Beau Miller, 42. “It was just a really good moment.”

Still, 70-year-old Rick Miller could not abide measures passed by Houston, Dallas, San Antonio, Austin and El Paso to add protections for sexual orientation and gender identity to their nondiscrimination codes, as hundreds of municipalities nationwide have done.

The elder Miller is an executive of an electricity delivery firm and lives in the Houston suburb of Sugarland. A retired Navy captain who once commanded a carrier attack squadron, he still keeps his salt-and-pepper hair cropped short enough to recall his military background.

Gays, he said, have “become a protected class” whose status is “discriminatory toward me” and other Christians.

“I’m a person who believes in individual liberty and freedom,” Rick Miller said “and I don’t discriminate personally.”

Though his repeal bill is languishing in a House committee headed by a Houston Democrat, he vowed, “We’re standing strong on this.”

Other lawmakers sympathize with the family’s personal strain.

“It’s certainly something they both believe strongly and it’s unfortunate,” said Republican Rep. David Simpson, one of Miller’s bill’s co-sponsors.

Beau Miller, the middle of three children, grew up in four southern states as his dad’s military career kept the family moving. He graduated from high school in Virginia while his dad was stationed at the Pentagon. The family was deeply religious and attended Baptist or Episcopalian churches depending on where they were living.

In college at Louisiana State University, Beau played trumpet, led a campus Republican group and campaigned for George H.W. Bush before going to the University of Texas law school, where he was president of his class.

He came out at 27, when his parents asked why there weren’t more women in his life.

“Dad’s not a guy who gets angry. He was upset,” Beau Miller said. “Dad had a lot of questions. There were concerns. ‘This is not the life that he wants for his son,’ that type of thing. But he’s not a yeller.”

In 2006, the younger Miller was diagnosed with HIV. It took three years for him to tell his parents, and he did so only after co-founding LIVE Consortium, a nonprofit that helps reduce the stigma surrounding people living with the virus.

Rick Miller said he supports his son in all aspects of his life except his sexual orientation. “I personally feel that’s a chosen lifestyle.”

His son says that doesn’t make sense.

“I can no more be straight than my father can be gay,” he said. “And so, selective support is an interesting idea for a parent, I think.”

The language for Rick Miller’s bill was presented to him by a Texas family values group, but Beau Miller said he thinks other conservatives saw his father as an ideal sponsor for the bill since “there’s a theory that if Rick Miller can do this, and his own son is gay, it creates greater weight that this should happen.”

“It’s made me embarrassed to have your father on the wrong side of history,” he said.

But after someone sent Rick Miller an email calling him a bigot, Beau Miller posted an online message imploring opponents of the bill not to “match hate with hate.”

Victoria Cook, a longtime friend of Beau Miller’s who also knows his parents, said the family’s bonds are still holding firm.

“Beau took the high road and decided to do everything he could to keep a good relationship with his parents,” she said “even as they consistently rejected an essential part of who he is as a person.”

Of whether he and his son could remain estranged permanently, Rick Miller said, “From my wife and I’s prospective, it’s up to him. We’ll want to talk to him. We’ll want to get together with him at Thanksgiving and Christmas.”

Beau Miller said their relationship will heal, but it will take time.

“I do love him, and I love him unconditionally,” he said. “I don’t have to like everything he does.”

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