A Phoenix woman is facing felony charges after police said she used drugs and abused a 3-month-old boy weeks ago.

The investigation into Dajsia Walker, 24, started on Dec. 26 after the victim began twitching the day before, and it grew significantly worse the next morning, so he called 911.

The infant was rushed to Phoenix Children’s Hospital, and staff said the boy had multiple brain bleeds, a right skull fracture and other healing fractures on his ribs and a leg, court documents said. Doctors believe the brain injury was due to a lack of oxygen.

Police talked to Walker and the father. The father said he was away on Christmas Eve and part of Christmas Day. He noticed the baby twitching at his parents’ house on Christmas Day.

Walker was the main person taking care of the baby during the time the injuries likely happened, police said.

During the investigation, Dajsia Walker first denied knowing how the boy got hurt. She admitted to using marijuana and, after a search warrant, admitted she had used cocaine in the past but not since the children were born.

Police said a hair test for drugs on Walker that detects narcotics for the past three months came back positive for cocaine.

Court paperwork said the father passed a polygraph test, but Walker did not show up for her two polygraph appointments.

On Wednesday, Walker was arrested at an apartment on Seventh Street just south of Bell Road.

After she was read her rights, police said she told them she was the only one watching the victim on Christmas Eve and admitted to doing cocaine with a friend 24 to 48 hours before. She could not explain the baby’s injuries, police said.

She was booked into jail on two counts of child abuse. Her bond was set at $75,000.