Fossils from the skull of a Neanderthal child that likely had Down syndrome shed light into the collaborative and communal caregiving that likely aided the child to survive to about age 6 — unlikely for early hominins with congenital defects, according to new research.

The fossil fragments, excavated from the Cova Negra archaeological site in Valencia, Spain, were determined to be of Neanderthal child’s ear who lived up to 273,000 years ago and showed congenital malformations consistent with Down syndrome, according to a study published Wednesday in Science Advances.

When researchers did a CT scan of the small fragment of the temporal lobe, the bone where the inner ear is located, they reconstructed the inner ear that showed five abnormalities associated with Down syndrome, which had never been detected before in a Neanderthal, Mercedes Conde-Valverde, a paleoanthropologist at the University of Alcala in Spain, told ABC News.

“The only syndrome that is compatible with the entire set of malformations present in [the remains] is Down syndrome,” Conde-Valverde wrote.

What makes the fossil even more remarkable is that the female child lived to the age of about 6 and would have needed ample a lot of assistance to deal with her health difficulties, a notion that goes against the theory of Neanderthal culture of reciprocity, Conde-Valverde said — that caregiving emerged as a self-interested pact between participants who could reciprocate the behavior.

Neanderthals would tend to take care of or favor people were capable of return the favor or helping them in another way. But this Neanderthal girl — who suffered from health issues such as hearing loss, imbalance problems and vertigo — likely could not return the favor, so her survival appears to be bared purely on the altruism of the adults around her, Conde-Valverde said.

The child’s mother would have struggled to provide care while simultaneously keeping up with the daily challenges of a foraging lifestyle in the Paleolithic era, according to the paper.

Prehistoric children with congenital diseases had an uncertain path to survival to adulthood and could not be counted on for reciprocation, according to the paper.

The findings suggest that hominin caregiving emerged due to compassion rather than reciprocation, the researchers concluded.

Neanderthals, or Homo neanderthalensis, lived during the Paleolithic period lived between 430,000 and 40,000 years ago. They were “clever people” with big brains and buried their dead, Conde-Valverde said. The biggest difference to homo sapiens are the morphology of the skull.

“I think they are really humankind,” she said. “…with more research and more fossils, we will know that they were really similar to us.”