James Patrick Nemeth, 39, pleaded guilty in January to voluntary manslaughter and child abuse. He was sentenced after Superior Court Judge Joan Weber denied his motion to withdraw his plea based on a claim that he was misled by his trial attorney.
Nemeth pleaded guilty to the May 2012 death of Louis Oliver and choking two of his sons, hitting them with a belt and punching one of them in the stomach.
"You assaulted and shook my son to death,'' Cristina Oliver told the defendant. "You are evil. My family has been altered forever.''
Michael Oliver, the victim's father, called Nemeth a "bottom-feeder and a failure,'' saying he abused at least four other children. The father said his son's death serves as a catalyst for bringing changes to the childcare and daycare system so that allegations of abuse at such facilities will be investigated and made public.
Deputy District Attorney Nicole Rooney said Nemeth wouldn't have been licensed had he not lied to officials about his past.
According to evidence presented at his preliminary hearing last year, Nemeth was alone with Louis Oliver for about an hour on the afternoon of May 23, 2012.
A San Diego police detective testified that Nemeth said he woke the child up from a nap and found him to be a "little limp,'' putting him in a car seat while he tended to other children. Nemeth told investigators that when he turned his attention back to Louis, he found him unresponsive and not breathing.
Rooney said Nemeth lied about when he called 911, dialing the emergency number only after he talked on the phone with his mother for four minutes.
The toddler was pronounced dead the next morning. Doctors testified that he had severe retinal hemorrhages and suffered non-accidental trauma.
Rooney said the defendant shook Louis about eight days before fatally injuring him, but the child survived that shaking.
Another San Diego police detective testified that Nemeth's adult daughter told investigators that her father had a temper and yelled at children at his daycare facility, where she also worked. She told police that her father would become frustrated when babies cried, the detective said.
A former employee told authorities that she called Child Protective Services after seeing Nemeth push a boy down a hallway and press the boy's nose against a wall, a district attorney's investigator testified.