MARYSVILLE — An Everett woman broke down a door trying to rescue her 11-month-old grandson from his father as the man tried to use a paring knife to circumcise the infant on the bathroom floor of her apartment.

The family of Christopher Eaves told investigators that he began experiencing mental health problems in October and twice has been involuntarily hospitalized. He’d recently stopped taking his medications and the family was looking into having him re-hospitalized, Snohomish County deputy prosecutor Lisa Paul wrote in court papers.

Paul on Friday charged Eaves, 26, with second-degree assault of a child. He is accused of cutting his son Feb. 2.

Eaves’ family told investigators that he’d become obsessed with having his son circumcised. He and his wife checked into having the procedure done by a doctor, but Eaves took matters into his own hands, Paul wrote.

Eaves’ wife had become so concerned about his behavior that she wouldn’t allow him to be home alone with their child. On the day of the attack, Eaves’ mother was babysitting the child while the boy’s mother was at work. Eaves was there, along with his sister.

Investigators say Eaves took the boy into the bathroom and locked the door. The boy’s grandmother used a butter knife to unlock the door but Eaves blocked her entrance.

She could see that the boy was laying on the ground and Eaves had a knife in his hand. She broke the door of the hinges and wrestled with Eaves, trying to get the knife away from him. He was too strong but she convinced him to hand over the knife when she told him that she’d help. The woman grabbed the infant and ran to the kitchen to call 911.

Eaves followed the woman, grabbed another knife and snatched the boy away. He began to circumcise the boy, Paul wrote. Eaves’ mother jumped on her son’s back in an attempt to stop him.

The woman was only able to get the boy after Eaves stopped cutting, court papers said. She grabbed the child and ran outside.

Everett police arrived and arrested Eaves.

Doctors told police the boy needed further evaluation by a urologist to determine if there were any potential lasting complications, Paul wrote.

Eaves is being held in the Snohomish County Jail on $250,000 bail.

Diana Hefley: 425-339-3463; hefley@heraldnet.com.