ABC News' Diane Sawyer, left, speaks with Jaycee Dugard in Ojai, Calif., during her first interview. (JILL BELSLEY/ABC NEWS VIA ASSOCIATED PRESS)

Jaycee Lee Dugard, who was kidnapped when she was 11 years old and held captive for 18 years, gave her first interview to ABC’s Diane Sawyer. But pieces of the interview, which will air Sunday, have been released, showing a remarkably composed Dugard.

Dugard, who was raped by her captor, Phillip Garrido, described giving birth to her daughter when she was 14 in a backyard prison with no assistance. She didn’t know she was in labor at first, and was “just scared.” But after the baby was born, Dugard told Sawyer, “I felt like I wasn’t alone anymore. ... I had somebody else who was mine.”

In 1991, Dugard was abducted by Garrido on her way to school. Dugard was identified in 2009 as Garrido and his wife Nancy attended a parole meeting. Phillip Garrido was sentenced to 431 years in prison this June and his wife received 36 years to life.

When asked how she coped with the horrible conditions she was kept in, the 31-year-old said, “There’s a switch that I had to shut off.”

“You just do what you have to do to survive,” she continued.

Dugard has written a memoir titled, “A Stolen Life.” In it, she describes her kidnapping and the rapes she endured in detail, according to the Associated Press, who obtained a copy. Despite overcoming so much, Dugard writes that she is “still afraid it will be taken away.”

Watch a clip from what promises to be an extremely emotional interview below: