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Tristan Thompson is mourning the loss of his beloved mom Andrea Thompson on Thursday.

Sources tell TMZ, Andrea was rushed to a hospital after suffering a heart attack in Toronto, Canada, on Thursday. She was pronounced dead on arrival.

Tristan, 31, and his ex-fiancee Khloe Kardashian took a private jet to his native Toronto to be with his family.

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Andrea, 49, was the sole caretaker for her special needs son, Amari Thompson, who suffers from epilepsy. The “Amari Thompson Foundation” was founded to help Epilepsy Toronto provide support to individuals and families through counseling.

Andrea leaves behind her 2 sons and four grandchildren. She never met her grandson, Theo, by personal fitness trainer Maralee Nichols.

Khloe, 38, welcomed Tristan’s youngest son by a surrogate last year. She is also mom to Tristan’s only daughter True Thompson, 4, who is pictured below with his mom.

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