ELK GROVE (CBS13)  — Caretaker Aaron Gacilan is behind bars facing an involuntary manslaughter charge in connection to the death of 18-year-old Alex Sanchez.

Aaron Gacilan (credit: Elk Grove Police Department)

Sanchez died last month after suffering a head injury while under the care of Gacilan at an Elk Grove Adult Residential Facility.  ‘

Police said Gacilan kicked Sanchez in the head several times until he went limp but was conscious.

“I don’t understand why, why would you hurt one of the most vulnerable of the human race,” said Sanchez’s grandmother Amy Duarte.

Duarte says her grandson was mentally disabled following a crash as a baby.

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A woman who didn’t want to go on camera says she was unaware of the situation at the home until officers showed up to her neighborhood recently.

“But when we saw the police, I said ‘something happened in there,’” she said.

Records show the adult residential facility where Sanchez was receiving care got its license just five months ago and that Gacilan was the CEO. The California Department of Social Services oversees care homes and has now launched an investigation.

CBS13 went digging for answers on what it takes to get a license. The process to obtain a license involves several steps including at least 35 hours of training on subjects including:

-Psychosocial needs of residents

-Physical needs of residents

-Drug administration

-Nonviolent crisis intervention techniques

“Our role is to be resident-centered,” said Sergio Landeros.

Resident advocates say what happened is heartbreaking and they are continuing to push for better solutions to prevent incidents like the one that took the life of Sanchez.

“It’s a system that we need to pay closer attention to, to ensure the quality of life for these folks in these facilities,” Landeros.