Billie Jo Lloyd, 25, of the 100 block of Meier Road near Old Monroe, was charged Thursday with first-degree assault.

Authorities say Lloyd struck her 15-month-old son, Gaven, causing severe head injuries.

Lloyd tried to blame the toddler's injuries on an accident while the child was at a baby sitter's home Tuesday, investigators say.

The state has taken custody of the child. It is not yet known whether his injuries are permanent. Lloyd was jailed Thursday in lieu of $100,000 bail.