Popsugar Celebrity Celebrity Friendships Demi Lovato's Birthday at Ariana Grande Concert 2019 Demi Lovato Rings in Her 27th Birthday With Ariana Grande: "I Love You Tons" 20 August 2019 by Monica Sisavat Solís View On One Page Photo 5 of 10 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 5 Previous Next Start Slideshow Celebrity FriendshipsCelebrity InstagramsAriana GrandeCelebrity BirthdaysDemi Lovato