A Staten Island teen is facing child-endangerment charges in connection with the beating death of her boyfriend’s 2-year-old son, authorities said yesterday.

But Josiah Taylor’s father, whose name has not been released, has also been questioned, and investigators said more charges are expected.

Josiah was found dead at about 1 p.m. Tuesday in a house on Mosel Avenue in Concord. He’d been left in the care of Cynthia DuBoise, 18, who was charged partly because she waited too long to call 911 after Josiah lost consciousness, sources said.

She also made “incriminating statements” to officers, said a source who declined to go into detail.

An autopsy found that Josiah died of battered-child syndrome. His injuries included new and old bruises on his sternum, back and legs and bite marks on his arms, a source said.

The source of the bite marks was unclear.

“The injuries were in various stages of healing, and the injuries occurred over a period of time,” said a spokesperson for the Medical Examiner’s Office.

The city Administration for Children’s Services is also investigating.