A woman who drowned her 6-year-old daughter because she believed the girl was a demon was sentenced to 23 years in prison for first-degree murder.

"At the time of my action, I did not realize I was doing anything wrong," Samara Spann, 32, wrote in a letter to King County Superior Court. "I wish I could rewrite the script, because then my daughter would be living."

Spann, 32, formerly of White Center, admitted to investigators that on Dec. 31, 2004, she grew frustrated when her daughter, Kyeimah, wouldn't go to sleep and repeatedly interrupted her phone conversation. She drew a bath and drowned the girl.

Two days later, she told investigators, she took an ax to the body, decapitating it and tossing the remains off a bridge into a body of water. The girl's remains were never found.

For six months after the death, Spann claimed she had sent the girl to live with her father. Investigators persuaded her to confess.

Her sentence was near the middle of the standard 20- to 27-year range. King County Deputy Prosecutor Kristin Richardson agreed that Spann had a troubled past, but said the woman just wanted to get rid of her daughter. Spann told sheriff's detectives the girl needed "too much damn attention," Richardson said.

Her attorney, Virginia Faller, said Spann was abused as a child and suffered severe mental problems. Judge Joan DuBuque agreed Friday, but said, "No child deserves to be treated in the way that this child was treated."

Spann's father, Gary, asked DuBuque for the maximum sentence.

"We begged you, we fought you, we did everything we possibly could to get her away from you," he said, addressing his daughter. "You were worse than Kyeimah when you were little, but you're still here."

Spann was sent to Western State Hospital several times for mental-health and competency evaluations, but was ultimately deemed competent. She pleaded guilty in March.