MILTON, Mass. -- A girl celebrating her fifth birthday was stabbed and killed by her brother, who had also killed her sister and attacked a third, police said.

Kerby Revelus, 23, was shot and killed by police who broke down the door to the home after receiving a 911 call from the surviving girl.

The horrific scene unfolded in a home at 7 Belvoir Road in Milton Saturday afternoon.

Revelus had killed his sisters Samantha, 17, and Bianca, 5, with a kitchen knife, police said. He had turned to attack Saraphina, 9, when he was shot by police.

"What we have is an awful, awful tragedy that has struck one family extremely hard," said Norfolk District Attorney William Keating. "It's hard to imagine the grief to the Revelus family."

Keating said Samantha Revelus had told her sister to call 911.

Police did not immediately release Sarafina Revelus' condition, but she is expected to survive. She was with her parents at Boston Medical Center.

"We have her in our prayers. That's what's important," Keating said. Samantha Revelus was a senior at Milton High School.

The children's parents were not home at the time. The mother collapsed in grief when she returned from work to find her house surrounded by crime scene tape and police.

In the home police found a birthday cake with five candles on it, Keating said.

Kerby Revelus had a history of domestic violence, police said. He was released from prison several months ago after a conviction in 2007 for a firearms charge.

"It's very horrific," Milton Police Chief Richard Wells said. "His intent was clear. He was trying his best to kill all of them." Wells said he did not know what led to the attack.

Four Milton police officers who entered the home were treated for trauma and stress after the attack.

"The officers walked into a scene of carnage," Wells said.