Updated

A Houston-area woman has been charged in the death of her 10-year-old son whose body was found in a cardboard box a year ago.

Tina Louise Madrid, 42, was arrested at her Texas City home Wednesday on a murder charge, The Galveston County Daily News reported. A coroner last week ruled the drowning of her son, Jonathan Singer, a homicide.

Jonathan had cerebral palsy and could not care for himself. Authorities said he was neglected and weighed only about 35 to 40 pounds.

Prosecutors said Jonathan's father, Jeffrey Singer, 46, left the boy alone in a bathtub while he went shopping. The boy drowned. His body was discovered last April in a box in the back of Singer's truck in Spring Branch, an area of west Houston.

Singer was charged with serious bodily injury to a child and is free on $50,000 bond, according to Harris County court records.

It wasn't immediately clear what part prosecutors believe Madrid played in the death. Online jail records do not list an attorney for Madrid, who was jailed and held under bond set at $50,000.

Police in Pasadena, another Houston suburb, visited Madrid's apartment in April 2011 after a call from a relative concerned for Jonathan's welfare. Officers were told the boy was fine and with his father, although they were not able to find either of them, police spokesman Vance Mitchell said

The next day officers were summoned to the west Houston home of Jeffrey Singer's father where Singer had parked his truck, where they found the child's body in the truck.

Police said Singer made statements about being responsible for the boy's death, and they arrested him. The child had been dead about five days when his body was found.

Child Protective Services had investigated the boy's welfare in 2010 and found no evidence of abuse or neglect. Child welfare officials doing a second check later were unable to find the family.

Click here for more on this story from The Galveston County Daily News.