Tristan Thompson is in mourning.
The NBA player's mother Andrea Thompson has died, E! News can confirm. According to TMZ, citing sources with direct knowledge, Andrea suffered a heart attack at her Toronto home Jan. 5. Tristan has since left Los Angeles to be with his family.
Khloe Kardashian—who shares daughter True Thompson, 4, and a 5-month-old son with Tristan—joined the athlete to "comfort and help him navigate what will be a very difficult time," a source told E! News.
"This was unexpected," the source added. "She was incredibly close to his mother, and like Khloe and the Kardashian family always do, they will come together and support their loved ones in their most difficult time of need. Tristan is the father of Khloe's kids and she and her entire family will always be there for him."
Andrea had a huge impact on Tristan's life, especially as his basketball career grew.
After Tristan was chosen fourth overall in the 2011 NBA draft, Andrea reflected on how her son made it all the way to the pros with help from mom and dad Trevor Thompson.
"Trevor is a truck driver. I drive a school bus," she wrote for the Toronto Star. "We work hard. In life you have to work hard to receive your blessing, everybody knows that."
But, according to Andrea, she "didn't have to tell Tristan anything to empower him. Tristan saw us always working hard, and he wanted to get ahead."
While celebrating Mother's Day 2020, Tristan shared a story to showcase the impact she had on him and his siblings including younger brother Daniel Thompson.
"It was a blizzard, it was terrible," Tristan recalled, detailing how she insisted they push through the storm to get to a basketball game. "My mom is a school bus driver so she knows how to handle the roads and everything. Daniel was crying, and he wouldn't stop, so I think he was hungry."
But never underestimate a mom on a mission. According to Tristan, Andrea decided to drive and breastfeed at the same time.
"Seeing her do that and be just a warrior and a champ and how much she was willing to sacrifice for me to get to that tournament so I could go play and do something that I love," he said. "I mean it just shows her love and passion for her kids."