(STMW) — In the summer of 2011, while he was supposed to be baby-sitting a 9-year-old relative, a west suburban man sexually assaulted the girl, according to prosecutors.

Nearly three years later, the girl told a doctor what had happened to her and on Thursday, Jose Antonio Merino, 37, was sentenced to 12 years in prison after pleading guilty to one count of predatory criminal sexual assault, according to the DuPage County state’s attorney’s office.

From June through August 2011, the girl was brought to Merino’s West Chicago home for baby-sitting when her mother went to work, prosecutors said. The sexual assault took place during one of those visits.

“During the summer of 2011, Mr. Merino was supposed to take care of and protect his young victim while her mother was at work,” state’s attorney Robert Berlin said in the statement. “But instead of keeping a watchful eye on her, Mr. Merino sexually assaulted her in a disgusting attempt to satisfy his own sick desires.

“He thought nothing of what effect his assault would have on her. He was only concerned about himself.”

It was not until March 2014, “during a visit to a health care professional when the victim disclosed what Merino had done to her,” prosecutors said. The doctor alerted West Chicago police.

On March 12, 2014, Merino was charged and ordered held on a $500,000 bond, and he has remained in jail since then. By law, he must serve 85 percent of his sentence and will have to register as a sex offender for life.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2015. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)