The 2016 NBA champion flew to Toronto to be with his family, accompanied by ex-girlfriend Khloé Kardashian for comfort.
Andrea had grown close to Kardashian, who has two children with Tristan Thompson.
Kris Jenner, Kardashian’s mother, confirmed Andrea’s death in an Instagram post on Friday.
“I am heartbroken by the unexpected death of Tristan’s mother, Andrea,” Jenner wrote. “Tristan, Amari, Dishawn, and Daniel are in my thoughts, prayers, and heart. You were an incredible, dedicated, devoted, and selfless mother, as well as a loving, kind, and fabulous grandmother. You were such a blessing to your family!!! Andrea, I will miss you. I will miss your radiant spirit and incredible light. Thank you for always praying for us, lifting us up, and encouraging us. Rest in peace, lovely angel.”