The "thank u, next" singer shared a Facebook memory of her and the late rapper, who died of an overdose, celebrating Thanksgiving together last year.
In the selfie, which is garnished with a festive Thanksgiving filter, the two lay with their heads together. The post from 2017 was captioned, "a pie." On Grande's Instagram Story on Thursday, she wrote "you're v missed," on top of the throwback photo.
Miller died in his San Fernando Valley home on Sept. 7 from mixed drug toxicity. He was 26. The Los Angeles County Coroner confirmed that Miller was pronounced dead at the scene at 11:51 a.m. when emergency services responded to a 911 call.
Grande posted multiple tributes to Miller on social media following his sudden death. In one, she posted a simple black-and-white photo of him looking at the camera. In another, about a week after his death, she shared a video of the couple while they were dating.
"i adored you from the day i met you when i was nineteen and i always will. i can't believe you aren't here anymore. i really can't wrap my head around it," she wrote in the caption. "we talked about this. so many times. i'm so mad, i'm so sad i don't know what to do. you were my dearest friend. for so long. above anything else. i'm so sorry i couldn't fix or take your pain away. i really wanted to. the kindest, sweetest soul with demons he never deserved. i hope you're okay now. rest."
She retweeted a fan who sent her a video of Miller listening to her song "R.E.M." off her Sweetener album.
"his voice and laugh. he is supposed to be here. thank u for finding this," she replied to the fan.
She also mentioned Miller by name in "thank u, next," which she released days after she split from fiancé Pate Davidson this fall. On the track, which mentions several of her exes and how her past relationships have helped her grow, she sings, "Wish I could say thank you to Malcolm / 'Cause he was an angel."
Miller's death came in the midst of Grande's whirlwind romance with SNL actor Davidson. The two started dating weeks after Grande and Miller's breakup and became engaged shortly after. The engagement lasted a few months and the two broke up after Miller's death.
"What an interesting, challenging, painful and yet beautiful and exciting chapter of life," Grande tweeted earlier this month. "When it rains it pours but i'm embracing all of it. i'm excited for whatever else the universe has in store for me. she's growing n she's grateful."