Texas Teen Who Sued Parents Over Abortion Clash Back With Mom

June 14, 2013— -- It was a case that made national headlines – a pregnant 16-year-old in Texas emancipated herself from her parents because she felt they were pressuring her to have an abortion. Now, just four months later, that same teen is back living with her mother and awaiting the birth of her son.

In many ways Reagan (who has requested her last name not be used) is a lot like any high school student – excited about having her driver's license, planning for summer vacation and hanging out with her friends.

Watch the full story on "20/20: With Parents Like These" TONIGHT at 10 ET.

But unlike most of her high school peers, Reagan is no longer legally considered a child. Under Texas law, she is an adult. In February she made the agonizing decision to emancipate herself from her parents, who are divorced.

The high school junior took her parents to court in Harris County, Texas, to sever their parental rights after she became pregnant and argued with her parents over whether she should have abortion.

"I was furious with both of them," Reagan said in an interview with "20/20." "I wasn't trying to be a stubborn teenager."

Reagan had met her boyfriend, Evan, during summer vacation. A sophomore at a neighboring high school, he shared her love of horses and the outdoors. The two started spending more and more time together after Reagan got her driver's license.

"I've never dated someone who treated me good like that," said Reagan, who fell hard for the handsome 16-year-old. "I think me and him actually got close, really quick."

Reagan's mother, Denise Koen, talked to her daughter about sex and preventing pregnancy. "I said, If you're going to choose to have sex, then you need to ensure that you're going to protect yourself," said Koen. "We'll get you on birth control. I don't want you to set yourself up to fail."

But Reagan stopped taking her birth control pills – and soon after discovered that she was pregnant. She told Evan, who was shocked by the news.

"[I] wasn't expecting to be 16 and having a baby," Evan said.

Reagan held off telling her parents. "I didn't know what my mom was going to think," she said. "Especially Dad, you know, because, it's like your fear when you're a teenage daughter is, Oh my God, my dad!'"

After she broke the news, her father, Jeff Koen, was very upset.

"It's a mistake, done by kids that obviously don't know what they're doing," he said, referring to the pregnancy.

Reagan's mother said she and her ex-husband gave Reagan three options – abortion being only one of them. But Reagan told Evan and his parents that she was afraid her parents might force her to terminate her pregnancy. "She asked us to please help her," said Jaime Burnside, Evan's mother. "And I said, I don't know what I can do, but I'll figure out something."

Evan's parents contacted attorneys from Texas Center for the Defense of Life on Reagan's behalf.

The next thing Denise Koen knew, her daughter had obtained a temporary restraining order against her and her ex-husband.

"I looked at her, I'm like, Really?" recalled Denise. "Where did this come about?"

Within a week the emancipation of Reagan was underway. Both families went before a judge, and Reagan's parents signed an agreement to allow her to marry Evan, thus emancipating her.

In an exclusive interview with ABC News, Reagan's parents and her maternal grandmother, Diane Bailey, said they believed Reagan was manipulated by attorneys with an anti-abortion agenda, who used Reagan to publicize their cause.

"They are activists," Bailey said about the attorneys. "They want to make a sensation for themselves."

Reagan's family was frustrated, Bailey said, because no attempts at mediation were made, and Reagan's signature was legible on legal documents, revealing her identity.

"For us," Reagan's attorney, Steven Casey, told ABC News, the "lawsuit is, for lack of a better phrase, the nuclear option."

Meanwhile, Reagan was adjusting to the idea of being emancipated from her mom and dad.

"I had an idea of what emancipation was," she said. "But I never got, like, the whole gist of it."

Reagan broke off contact with her parents. She and Evan were living with his family and preparing to have the baby, due in September.

Then, in yet another surprise twist, just two weeks ago they moved out of the Burnsides' house and moved in with Reagan's mother.

"They made the choice to move back to my home," said Denise Koen. "I know we're going to have to take everything slowly, but it's such a blessing. I'm really, really pleased that she's back."

Watch the full story on "20/20: With Parents Like These" TONIGHT at 10 ET.