Former child actor Sophie Nyweide was pregnant at the time of her death earlier this month, according to a copy of her death certificate obtained by NBC News on April 24. Nyweide, known for her roles in “Mammoth” and “Margot at the Wedding,” was found dead at age 24 in a wooded area near Bennington, Vermont, on April 14, her death certificate said.

Authorities are investigating the death of Nyweide, who worked with filmmakers such as Darren Aronofsky and Noah Baumbach, as a possible unintentional overdose.