Babies in NICU celebrate 1st Halloween with sweet costume contest

A group of pint-sized patients in the NICU are celebrating Halloween in the most adorable way.

Parents were invited to dress up their little ones for the third annual costume contest at Advocate Children’s Hospital in Oak Lawn and Park Ridge, Illinois. The 40 participating babies ranged in age from less than a day old to 3 months old.

Deb Skopec, a neonatal outcomes nurse at Advocate, said some families have their babies in the specialized nurseries for four to six months.

"These parents really don't have any normalcy in their lives and a lot of times they're grieving ... it's not what they anticipated when having a baby," Skopec told "Good Morning America." "We like to celebrate the special times in one way or another -- to celebrate what Halloween would have been, only we shift it to the NICU."

"It's uplifting and yet at the same time it's healing," she added. "We are still monitoring the baby as close as ever [through] every celebration."

The parents of the children provide the costumes and work with the nurses and doctors to determine if their baby is medically fit to participate, a representative of Advocate told "GMA," adding that the event is optional. Advocate is one of many hospitals across the country that holds a Halloween costume event.

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The preemies were all photographed to give their families happy memories, despite not being home yet.

All babies who got in the Halloween spirit are featured on Advocate's Facebook page where people can vote for their favorite costumes and help families win prizes.

The photo with the most likes by Nov. 1 at noon will receive a $150 gift card to Target and runner-ups will take home gift cards up to $50 in value.