She also posted a sweet birthday message to Taylor on her Tumblr
, calling her a "sister." "Today one of my sisters turns 25," Lorde wrote. "Sure, she isn’t a reeeal sister, and I haven't known her thaaat long, but it feels like forever -- together, we've navigated our respective crazy years in work, in love, in friendship, and in growing up. I feel so lucky being part of this amazing circle of girls who are there for each other, dancing without inhibition, laughing for hours, and killing it at work, and we're pretty much all here 'cause of her. What I'm trying to say is, she's magic."