Former child star Evan Ellingson has died at the age of 35.

According to San Bernardino County Sheriff's Department records, Ellingson was found in his bedroom in Fontana, California, on Sunday. A cause of death has not been determined, pending an autopsy.

The San Bernardino County Sheriff's Department said Monday in a statement to USA TODAY that the Fontana Police Department is the primary agency investigating Ellingson's death.

Ellingson starred in the 2009 film "My Sister's Keeper" as Jesse Fitzgerald, the old brother of Abigail Breslin, whose character has acute promyelocytic leukemia, and teenage son of Cameron Diaz. The film also stars Alec Baldwin and Emily Deschanel.

Ellingson also starred in the short-lived ABC sitcom "Complete Savages" from 2004 to 2005, as Kyle Savage; Josh Bauer in Season 6 of the Kiefer Sutherland-led series "24"; as a kid marine in the 2006 Oscar-winning war film "Letters from Iwo Jima" directed by Clint Eastwood; as Kyle Harmon, the son of Horatio Caine and Julia Winston, on Seasons 6 to 8 on "CSI: Miami"; and appeared on episodes of "Mad TV" and "Bones."

His first credited role is in the 2001 drama film "Living in Fear" starring Marcia Cross and William R. Moses.

Ellingson has not had any film or TV credits since 2010.

Other stars lost this year include Matthew Perry, Suzanne Somers, Tyler Christopher and more.

More:Tyler Christopher, soap opera actor from 'General Hospital' and 'Days of Our Lives,' dead at 50