Kevin Mazur/One Love Manchester/Getty Images for One Love Manchester

Miller died of an accidental overdose in September.

Ariana Grande will never forget Mac Miller.

The 25-year-old pop star remembered her ex on Twitter on Saturday, after a fan sent her a video of an Instagram Live Miller had recorded in August. The rapper died less than a month later, on Sept. 7 of an accidental overdose of fentanyl, cocaine and alcohol. He was 26.

“His voice and laugh,” Grande wrote in response to the video, which saw Miller listening to her song, “R.E.M.” — even though they had split months earlier, and she was engaged to Pete Davidson at the time. “He is supposed to be here.”

“Thank u for finding this,” she added.

On Saturday night, Grande released her new song, “Thank U, Next,” which directly referenced her romance with Miller, among several other exes.

“Thought I’d end up with Sean/ But it wasn’t a match/ Wrote some songs about Ricky/Now I listen and laugh,” she sings in the track. “Even almost got married/ And for Pete, I’m so thankful/ Wish I could say, ‘Thank you’ to Malcolm /’Cause he was an angel.”

A source previously told ET that Grande was “devastated” by Miller’s death. “Although the two ended their relationship, Ariana always shared a deep connection with Mac and wanted nothing but the best for him,” the source said in September. “Ariana is very upset.”

The “God Is a Woman” singer opened up to her fans about coping with pain and trauma through therapy on Monday.

“In all honesty therapy has saved my life so many times,” she wrote on Twitter. “If you’re afraid to ask for help, don’t be. U don’t have to be in constant pain & u can process trauma. I’ve got a lot of work to do but it’s a start to even be aware that it’s possible. ?.”

See more in the video below.