The mother of Peyton Valiente, a boy who was severely injured at age 17 months while under the care of his babysitter in 2015, said Wednesday she was disappointed no one will be charged with her son’s assault.

Chelsea Valiente expressed her disappointment shortly after the Attorney General’s office announced that it would not be able to bring criminal charges in the case. “Anything short of conviction, I will never be 100 percent satisfied,” Valiente said.

But Valiente added that she appreciated the efforts of the AG’s office and a Honolulu Police Department detective in trying to revive the case. “It was tough because the initial work was so sloppy,” she said.

Valiente was referring to the initial investigation by HPD, which eventually acknowledged that the probe fell short of department standards.

At the time of Peyton’s assault, he was under the care of Manuela Ramos, who was married to then-HPD officer Mark Ramos. Mark Ramos has since retired from the force.

The case generated extensive media coverage after the online news site Civil Beat disclosed that HPD did not follow recommended procedures when it initially investigated Peyton’s injuries.

Attorney General Doug Chin subsequently agreed to take on the case. In July, Chin convened a grand jury to hear testimony in the case.

Manuela Ramos and her daughter, Theresa, appeared before the grand jury, but they asserted their Fifth Amendment rights against incriminating themselves, derailing any prosecution, according to Valiente and a spokesman for the AG’s office. Manuela Ramos was caring for Peyton in her home, and Theresa was also at the house.

Chin informed Peyton’s parents on Friday that a suspect could not be identified, precluding any criminal prosecution.

“It was difficult to have to break the news to the parents, Chelsea and Rey Valiente, that our findings did not result in charges against a perpetrator,” Chin said in a news release. “Despite the outcome, we hope they receive some comfort by the renewed efforts to identify Peyton’s assailant and bring that person to justice.”

Even though the AG’s office represented the Valientes’ last hope of a prosecution, a negligence lawsuit that the couple filed against the Ramos’ is pending.

Chelsea Valiente also said federal officials are investigating the way the state Department of Human Services handled Peyton’s case.

She alleged in an Aug. 28 letter to the U.S. Department of Health and Human Services that the state agency mishandled the case, wrongfully implicating her and her husband for the abuse and, when they were cleared, failing to hold the suspected perpetrator accountable. DHS identified Manuela Ramos as the alleged perpetrator in court documents.

Peyton is now 4. It’s not clear whether the severe head injury he suffered in 2015 will result in long-term effects.