Janelle Monae Dresses as 'Nightmare Before Christmas' at Children's Hospital

Janelle Monae brought the spooky season spirit to Children's Hospital Los Angeles ... dressing up as Sally from "The Nightmare Before Christmas" and spending time with patients!

Check out the photos shared by the hospital Thursday ... the musician went all-out with her costume for her special visit, during which she shared stories and painted with the kids.

And, it appears she stayed in character throughout her time at Children's Hospital L.A., making sure the Halloween vibes were in full swing.

Janelle's hospital visit was just the start of a Halloween full of treats ... 'cause later Thursday, she changed into an epic vampire costume to attend her Wondaween Halloween music festival Vampire Beach event at the Santa Monica Pier!

In case you're wondering ... Wondaween is a month-long Halloween-themed arts festival she founded with multiple happenings across Los Angeles.

The "Make Me Feel" hitmaker has already celebrated by dressing up as the Cat in the Hat, Beetlejuice, and more.