Scott Disick's mother Bonnie Disick died last week at the age of 63, E! News reported.

Her cause of death has not yet been revealed.

Scott, an only child, was raised by his mother Bonnie and father Jeff Disick in Eastport, Long Island. Scott and his long-term girlfriend Kourtney Kardashian, also the mother of his children Mason and Penelope Disick, were in New York to attend the funeral this week.

"Scott was very close to his mother," a source close to the family told Radar Online. "It was a small affair. There was just a handful of people. No other Kardashians beyond Kourtney attended. But the entire family is saddened with the news of Bonnie's passing. They loved her so much."

Scott is said to be "devastated" at the loss of his beloved mother, according to the family insider. He has not publicly commented on his mother's death.

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Bonnie made an appearance in Kourtney & Kim Take New York. Kourtney, Kim Kardashian and Khloe Kardahian took Mason to visit Scott's parents in the Hamptons. Kourtney famously called Bonnie a hoarder and Scott got upset when his girlfriend tried to move furniture around and pack things away in his parent's home.

Kourtney gave birth to Mason in December 2009 and their daughter Penelope in July 2012. 

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Kourtney was seen at LAX airport heading to New York on Oct. 30. She and Scott have since been seen in New York City at several different outings. They were last photographed arriving at LAX on Thursday returning from New York.

The couple were not present when her siblings celebrated Kris Jenner's birthday in California this week.