On Sunday, Rivera's ex-husband, Ryan Dorsey, paid tribute to the late star by posting a photo of her enjoying dessert with their son, 5-year-old Josey.
"We can’t say the word happy but we’ll say thank you for being a mother & giving me this sweet amazing boy," Dorsey, an actor who was married to Rivera from 2014 to 2018, wrote.
The poignant post struck a chord with some of Rivera's former Glee co-stars. Jenna Ushkowitz responded with a series of red heart emojis, while Heather Morris — who played love interest and fellow cheerleader Brittany to Rivera's Santana — wrote, "This broke me. I love you."
Dorsey's Mother's Day tribute comes months after he marked what would have been her 34th birthday on Jan. 12.
Since her death, Dorsey has held sole custody of Josey, who was found napping in his life jacket aboard the pontoon boat his mother had rented for a three-hour excursion on Lake Piru in Ventura County, California. Rivera, whose body was recovered five days later, is believed to have saved her son before being pulled underwater, with Ventura County Sheriff Bill Ayub saying at a press conference that she “must have mustered enough energy to get her son back on the boat, but not enough to save herself.”
Dorsey has praised their young son for his "resilience," writing this January that "I couldn't be any prouder of someone. At such a young age, he's endured more than anyone should at 5 years old...
"You're so strong, so brave, and so kind. I will always be proud of you," he added.
Related: How Naya Rivera's family and co-stars paid tribute on her birthday
Read more from Yahoo Entertainment: