ATLANTA (CNN) -
Surrogate mothers can help bring joy to couples who otherwise cannot have children on their own.
But the legal agreements between surrogates and biological parents can force both sides to make difficult, painful choices.
Crystal Kelley was thrilled when a couple hired her to be their surrogate and carry their baby.
The husband and wife were ecstatic, too.
"She said pray for a little girl. I want a little girl," Kelley said.
Ultrasounds halfway through Kelley's pregnancy showed the baby girl growing inside her had severe heart defects, a brain abnormality and other medical problems.
"They said she had a less than 25 percent chance of being able to have a normal life," Kelley said.
Inside Hartford Hospital in Connecticut, the heartbroken parents asked Kelley to have an abortion.
"I refused. I couldn't do it. I was the one who was feeling her kick and squirm. I knew she had a fighting spirit. And I wanted to fight for her," she said.
The parents pleaded with Kelley. Genetically, this was their baby. She was just carrying her.
"They said they didn't want to bring a baby into the world only for that child to suffer," Kelley said. "They said I should try to be God-like and have mercy on the child and let her go. I told them it wasn't their decision to play God."
Kelley was a single mom. Money was tight.
Through the surrogacy agency, the parents said they would pay her $10,000 to have an abortion.
"In a weak moment I asked her to tell them that for $15,000 I would consider going forward with the termination," Kelley said.
The parents refused her request, and she said she quickly regretted asking for the extra money anyway. She said, deep down, she knew she could never abort under any circumstance.
The parents didn't respond to repeated calls or emails, and they have not been named.
Legally, they couldn't force Kelley to have an abortion.
So they made a proposition to her: If you have this baby, we'll give her up and she'll become a ward of the state.
"I'm not going to let her become one of those forgotten disabled kids that get lost in the system," Kelley said.
Without informing the parents, she secretly left the state.
"I packed up my van. Everything that I could carry. Threw my kids in the car and we drove for two days to Michigan," Kelley said.
Under Michigan law, Kelley would be the baby's mother.
"I can't tell you how many people told me that I was bad," she said. "That I was wrong; that I should go have an abortion; that I would be damned to hell."
She spent the final months of her pregnancy in Michigan and gave birth last June.
The baby is now 8 months old.
Along with her cleft lip and palate and a misshapen ear, she has severe brain and heart problems.
She'll need several risky surgeries to survive, but in many other ways she has developed like other babies. She smiles, babbles and grabs for toys.
"She's still a happy little girl who's going to bring joy into the lives of everyone who knows her," Kelley said. "It gives me a lot of joy. And I know that every single thing that I did was worth it."
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