WORCESTER (CBS) — The mother of a Fitchburg boy found dead in 2014 pleaded guilty to assault charges separate from the boy’s death.

Elsa Oliver changed her plea to guilty Tuesday, admitting to abusing her two other children. She pleaded to two counts of reckless endangerment of a child and assault and battery.

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In addition, the charges against her in relation to her son’s death were dropped.

Elsa is the mother of Jeremiah Oliver, a 5-year-old Fitchburg boy whose remains were found in a suitcase off I-190 in Sterling in April 2014.

Jeremiah Oliver. (Photo credit: WBZ-TV)

The boy’s death was officially ruled a homicide in February 2016, though nobody has yet been charged in his death.

The charges she pleaded guilty to were related to Jeremiah’s brother and sister.

She was sentenced to seven and a half years in prison–but has already been behind bars for three and a half years and will be credited for that time.

She refused to say anything in court, and no family members showed up.

Prosecutors say Oliver required the children to stand in a cold shower or kneel for extended periods of time.

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Elsa Oliver in court Tuesday.

Her defense said she pleaded guilty because she didn’t want to subject her children to a trial of any kind.

Elsa was set to go on trial later this month on these charges, as well as others–including kidnapping and assault and battery with a dangerous weapon.

But Early’s office said those charges which were related to Jeremiah’s death were dropped “to allow the death investigation to continue and to eliminate any possible double jeopardy claim in connection with his death.”

Worcester DA Joe Early’s office said the investigation into Jeremiah’s death “remains active and ongoing,” and officials say that case will continue moving forward.

Alberto Sierra. (Facebook)

Elsa’s boyfriend, Alberto Sierra, pleaded guilty last week to abuse charges unrelated to Jeremiah’s death and was sentenced to prison.

He had previously been charged with kidnapping and assaulting Jeremiah, but those charges too were dropped.

WBZ NewsRadio 1030’s Lana Jones reports

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