LOS ANGELES (CBSLA.com) — A Newhall man was charged Tuesday with sexually assaulting and killing his 19-day-old daughter.

Matthew Brendan Warner, 30, faces one count each of murder, assault on a child causing death, torture, oral copulation or sexual penetration with a child 10 years or younger and aggravated sexual assault of a child, the Los Angeles District Attorney’s Office said.

Warner and the child’s mother reported Friday night that their daughter, Ellorah Rose Warner, was missing from their Newhall home, the sheriff’s department said.

Deputies responded to their apartment in the 21300 block of Alder Drive to investigate the circumstances surrounding the missing child.

The infant’s body was then discovered around 7:30 a.m. Saturday in the cab of a truck parked in a lot in the 20600 block of Newhall Avenue.

That afternoon, the child’s father, who reportedly led deputies to the location, was arrested on suspicion of murder.

“According to the felony complaint, the murder and sexual assault happened on Jan. 23,” the District Attorney’s Office said.

The infant’s grandmother told CBS2/KCAL9 that she heard Warner use an unusual and stern tone with the child on the morning of the alleged crime. She then heard a weak, muffled cry coming from the bedroom.

Nan Alison, the child’s maternal grandmother, spoke outside of court Tuesday.

“I hope that every minute of the rest of his existence he is burdened with guilt for what he’s done,” she said.

Warner’s mother, Victoria Law-Thomson, says her son could could never have hurt his daughter.

“He was very protective, gentle. I mean, she was his light,” Law-Thomson said.

The child’s autopsy is not yet complete.

Warner is being held on $2.25 million bail and faces a maximum of life in state prison if convicted of all charges.

He will return to court on Feb. 18 for arraignment.

A memorial was held for the newborn Tuesday night in Newhall, where dozens paid their respects.