MISSING MILLER: American pop singer Ariana Grande did not forget her late ex-boyfriend Mac Miller's birthday. Miller, who would have celebrated his 27th birthday last Saturday, died of a drug overdose in September last year. Grande took to Twitter early last Saturday to post a simple message "miss u" , which many fans believed was a tweet for Miller. Later in the day, she posted on her Instagram story two photos of her with Miller. Grande and Miller dated for about two years before they ended their relationship in May last year. She then dated comedian Pete Davidson before the couple called off their engagement and split in October.