The biting of Julia’s mother occurred on Oct. 4, 2010. Sierra, who had moved in a month earlier, was arrested by Homestead police on domestic battery charges. In a court petition to keep Sierra away filed that day, Machado said the two had argued and she had threatened to call the police. Sierra grabbed her cellphone and “punched her on the hand” causing the phone to fall. When she tried to grab the phone again, Sierra bit her and “slammed her against the closet wall.” Machado also said Sierra had repeatedly kicked her car door a week earlier, and had kicked her in the stomach as she tried to get in the car. She said Sierra was on either drugs or alcohol when the assault occurred.

Ten days after she filed that petition, Machado withdrew it. But investigators responding to the complaint had found 79 grams of Ecstasy, and a stolen 9mm Smith & Wesson pistol, as well as ammunition.

Sierra was given a year’s probation, which he served under house arrest — in the same house where Machado and her kids resided.

Sierra was still under house arrest on Oct. 24, 2011, when the biting incident involving Julia occurred. Members of the Child Protection Team were unequivocal in their findings: “This is a [6] year old girl with an adult bite mark on her left arm,” the team reported. “In my opinion, this case represents an inflicted injury that rises to the level of child physical abuse.”

The Miami-Dade Police Department’s disposition: “unfounded.”

“My investigation revealed that, while playing with the children, [Sierra] playfully bit [Julia] on the arm, leaving a mark,” Detective Claude Larochelle wrote on Nov. 28, 2011.

However, police again found a gun in Machado’s house — a violation of Sierra’s probation — and they sent him to jail for 364 days. He served half of that.

The brutal deaths of Machado, Julia and Daniela followed his release by five months.