She didn't want her baby's father to go to prison.
"By law it was statutory rape, but to me it wasn't," Brittany Koerselman said about finding out in 2014 that she was pregnant at 15 with her 21-year-old boyfriend Jeremie Rook.
"He was part of the family, they called him their son," she said regarding her parents opinion of Rook.
By the time she was eight months along, the police began looking into the pregnancy and Rook faced possible statutory rape charges.
As Iowa residents, she couldn't legally marry Rook, but Missouri law allows 15-year-olds to marry with the consent of just one parent. Koerselman said that despite feeling way too young to marry, she didn't think that allowing Rook to go to prison would be the best solution for her or her child.
"I was never happier in my life than those two years before we had to get married," Koerselman said. She explained that she had been in love with Rook for two years before she got pregnant, and that it wasn't just a sexual relationship.
But by 18, she was divorced.
Watch Koerselman and Rook's story: