Sources: Julia Roberts’ half-sister left long suicide note to actress

LOS ANGELES – Julia Roberts’ younger half-sister, Nancy Motes, 37, was found dead on Saturday of an apparent drug overdose, her family said. The death is being investigated as a suicide.

Multiple sources tell FOX411 that a lengthy letter was found following Motes’s death, and that much of its contents were directed at her older sister. The letter was given to the coroner, sources said, and released to the family on Tuesday.

“The letter was a lengthy indictment of Julia’s behavior towards Nancy,” said an insider.

A spokesperson for the LAPD was not able to confirm that a note was found and said that was a matter for the coroner. The coroner’s office did not immediately respond to a request for comment.

According to sources close to Motes, who worked in the entertainment industry as a production assistant on Ryan Murphy’s “Glee” and later “American Horror Story,” bad blood had been brewing between her and Roberts for many years.

We’re told Motes struggled with her weight, which – according to sources – led to tension between the two.

“Nancy always felt that Julia was embarrassed by her,” said a source, who grew up with Motes in Atlanta and remained close to her.

Motes attempted to have her own acting career several years ago, another sore point between the two, but soon abandoned Hollywood for her hometown of Georgia. However, she returned to Los Angeles about three years ago after meeting her fiancé John Dilbeck, a former real estate assistant turned location scout, through friends.

The couple had planned to be married in May. The estrangement between Roberts and Motes grew deeper when Roberts said she was not planning to attend the nuptials, according to our sources.

Sources say the situation was further compounded by Roberts’ dark comedy “August: Osage County,” which explores drug addiction, death and dysfunctional families. Roberts is up for the Oscar for Best Supporting Actress.

“That was very hard for Nancy to see,” said an insider. “She was, for the most part, a really happy and bright woman. But relations with her sister really upset her, and have for years.”

Motes was hardly quiet about her relationship with Roberts.

Last August, she gave an interview indicating that she was estranged from the Hollywood star and claimed that her famous sibling routinely tortured her about her weight.

“When I was in high school and she was an adult, she would just let me know that I was definitely overweight,” Motes said, according to the New York Daily News. “It just makes me feel incredibly hurt and very sad.”

Motes also reportedly sent out a wave of angry tweets in the weeks leading up to her death, some of which have apparently since been deleted by a family member.

“So my ‘sister’ said that with all her friends & fans she doesn’t need any more love. Just so you know ‘America’s Sweetheart’ is a B**ch!” Motes reportedly tweeted on Jan. 20, in reference to Roberts’s starring role in the 2001 film “America’s Sweethearts.”

“Do you want to be a fan of someone so cruel? She’s not even that good of an actress. Happy you totally F**ked with me?”

Roberts was scheduled at attend the Oscar Nominees luncheon and make an appearance on “Jimmy Kimmel Live” on Monday night, but canceled both in the wake of Motes’ death.

Multiple news reports indicate that the “Pretty Woman” star had long been concerned for her sister and attempted to get her to rehab several times, to no avail. The New York Post reported that the famous actress endured something of a “private struggle” with her late sibling, and disapproved of her upcoming marriage.

A rep for Julia Roberts, as well as brother Eric Roberts – also an actor – did not respond to multiple requests for comment.

Follow @holliesmckay on Twitter