Sophie Nyweide. Photo:

Scott Wintrow/Getty 

Child actor Sophie Nyweide was pregnant when she died unexpectedly last week, according to a death certificate obtained by PEOPLE. 

Nyweide, 24, died on Monday, April 14, according to the Vermont Department of Health.

She was found in a wooded area in Bennington, Vt., about 25 miles from her home in Manchester Center.

The circumstances of Nyweide’s pregnancy, such as her stage, were not immediately clear, though a source familiar with the investigation tells PEOPLE she appeared to be in the early stages. The Vermont Department of Health did not immediately respond to PEOPLE’s requests for further information.

The cause and manner of her death remain unknown but Bennington police previously said there is a possibility of foul play in her death. 

In a statement following her death, the Margot at the Wedding actor’s mother told TMZ that she believed her daughter was using drugs. 

Bennington police told PEOPLE in a statement they are looking into Nyweide’s death as “a possible unintentional overdose,” and are investigating it due to its “untimely” nature.

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