A Vancouver woman admitted Monday that she coached her two children — beginning when they were 4 and 8 years old — to fake retardation so she could collect Social Security benefits on their behalf.

Rosie Costello, 46, pleaded guilty in U.S. District Court to conspiracy to defraud the government as well as Social Security fraud. Her son, Pete Costello, 26, pleaded guilty earlier this month, but the U.S. Attorney's Office in Seattle said Monday that authorities had not located her daughter, Marie.

According to the plea agreement, Costello began coaching her daughter at age 4, and later used the same ruse with her son. He continued to feign retardation into his mid-20s — picking at his face, slouching and appearing uncommunicative in meetings with Social Security officials.

The scheme came to light last year after Pete Costello got a traffic ticket while driving away from the administration's Vancouver office, then was videotaped acting normally when he contested the ticket in court.

Rosie Costello admitted that she collected more than $280,000 in benefits, beginning in the mid-1980s. Most were paid by Social Security, but the state Department of Social and Health Services paid $53,000.

Pete Costello is scheduled to be sentenced May 11 and faces a standard sentencing range of six months to one year in prison, as well as $59,000 in restitution. Rosie Costello is scheduled for sentencing May 17; her standard sentencing range was not immediately available, but in the plea agreement she agreed to repay the government.

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