Brooklyn Saechao celebrated her first birthday a week before she died

A Gresham man pleaded guilty to first-degree manslaughter Thursday, June 21, in the killing of his girlfriend's baby last summer.

Jeffrey Edward Locker, 22, entered the guilty plea before Multnomah County Circuit Court Judge Eric Bergstrom. The plea includes an agreement that he will serve 18 years in prison, but he won't be sentenced until July 23, said Charlene Woods, senior deputy district attorney.

In his plea petition, Locker admits to causing a head injury to 1-year-old Brooklyn Saechao in their Gresham apartment in the 16400 block of Northeast Russell Street on Aug. 2, 2011. The girl's mother, Jamie Saechao, was at work at the time.

He called 9-1-1, and an ambulance rushed the baby to a Portland hospital, where she died two days later.

Police found Locker the next day driving north of Milton-Freewater in Eastern Oregon, reportedly heading toward the Washington border, and arrested him without incident.

Court records indicate that Locker told police detectives the baby fell in the bathtub and hit her head.

She turned 1 just the week before her death.