Lara was instrumental in keeping the DJ AM legacy alive, most notably launching the DJ AM Memorial Fund.
A spokesperson for the estate confirmed the news with the website.
"It is with unbearable sadness that I can confirm that Lara Long, the sister to DJ AM passed away late Monday night, May 9th after a fierce four month battle with an extremely rare colon cancer. She was just two months shy of turning 41. Lara was responsible for keeping the memory of her brother alive with the creation of the DJ AM Memorial Fund. She was the driving force behind his eBay shoe sale as well as his record sales, working tirelessly to make sure he would not be forgotten."
The statement also touched on the glowing human being Lara was.
"Lara was an amazing woman, with a huge personality, a heart of gold and an incredible laugh. There are no words to explain how she will be missed. We ask that you please respect the privacy of the family at this most devastating of times.”
DJ AM was 36 when he was found dead in his New York apartment of an accidental drug overdose. A recovering addict, AM had worked to help other young addicts overcome their addictions in the MTV series "Gone Too Far," which aired following his death.
AM was reportedly taking anti-anxiety medication as a result of his fear of flying following the fatal plane crash he escaped last year along with friend Travis Barker. While experts say it is acceptable for some addicts suffering from pain and other trauma to use prescription medication — AM said he'd been sober for 11 years prior to his death — if used inappropriately or abused, prescription drugs can be just as dangerous as illegal narcotics, especially if used in combination with street drugs.