EDWARDSVILLE, Ill. (CBS St. Louis/AP) — Two southwestern Illinois parents are accused of tying a sock around the mouth of their crying baby.

Prosecutors in Madison County have charged 21-year-old Alexander Nicholas and 20-year-old Vanisha Nicholas of Alton with felony aggravated battery of a child after a five-month investigation. Authorities say the incident happened between March 15 and May 21.

The baby survived and has been in the custody of the state’s child-welfare agency.

“He seems to be doing well,” Alton Police Department Lt. Scott Golike told The Telegraph.

Police say officers dispatched to the family’s home May 21 noticed a mark on the child’s throat.

“He was a fussy baby. He was doing a lot of crying,” Golike told the paper. “They were unequipped to deal with the stress.”

The Nicholases couldn’t be reached for comment Tuesday. Court records don’t show whether they have an attorney, and they have no listed home telephone number.

They are being held on $50,000 bond.

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