The babies in the neonatal intensive care unit (NICU) at Saint Luke's Hospital in Kansas City, Missouri, will spend Halloween there instead of dressing up and heading around the neighborhood with family and friends. But that doesn't mean the holiday won't be special.

Nurses from the hospital and volunteers from the March of Dimes created handmade Halloween costumes for the 30 or so infants in the NICU.

NICU baby dressed as butterfly for Halloween An itty-bitty butterfly takes a nap. (Photo: Sally Morrow Photography and March of Dimes)

"Every day a child is in the NICU can be frightening and uncertain, but holidays are especially tough, as families miss the joy of celebrations together," Saint Luke's Director of Media Relations Emily Hohenberg tells MNN.

"Babies in the NICU may have been born too soon or too small, or with a medical condition that requires intensive care. Throughout the NICU experience, parents can be involved in their baby’s care in a variety of important ways."

NICU baby dressed as Batman for Halloween Itty-bitty Batman takes a break from his superhero duties. (Photo: Sally Morrow Photography and March of Dimes)

The babies' parents chose the outfits they thought most reflected their child's personality. There were butterflies, athletes and cheerleaders, and, not surprisingly, a lot of superheroes in the bunch. After all, these babies are superheroes to their parents and hospital staff.

NICU baby dressed like baseball player for Halloween Maybe this little slugger is dreaming of the Big Leagues. (Photo: Faces You Love Photography and March of Dimes)

It was the fourth year for the Halloween NICU dress up. It is so popular that the costumes come out for a new group of babies each Halloween. The parents are given the photos as a keepsake.

NICU baby dressed as Wonder Woman for Halloween Wonder Woman is ready to take on the world. (Photo: Schaumburg Photography and March of Dimes)

After the babies were dressed, volunteer photographers for the March of Dimes captured photos of the infants' first Halloween. The photographers are mothers of former NICU babies, so working with the tiny subjects is especially meaningful to them.

NICU baby dressed up as a butterfly for Halloween Even the smallest NICU babies still get to celebrate Halloween with their parents. (Photo: Faces You Love Photography and Marches of Dimes)

The parents were also given bags filled with treats, a Halloween book, and a "Trick or Treat, smell my feet" card featuring their baby's footprints.

NICU baby Kansas City Chiefs halloween This little one was dressed up to support the hometown team. (Photo: Sally Morrow Photography and March of Dimes)

Most of the babies seemed to nap through the big event. But the parents were happy to share the day with them.

Superman NICU baby Halloween Even the Man of Steel has to rest occasionally. (Photo: Sally Morrow Photography and March of Dimes)

Editor's note: This file was originally published October 2016 and has been updated with new information.

Mary Jo DiLonardo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.

Itty-bitty NICU babies dress up for Halloween
Hospitalized infants in Kansas City are photographed wearing sweet costumes for Halloween.