Given that all of these animals died within a tail's length of one another, it's likely that the adult was caring for the young, they said.

"Although it is possible that the individuals were all swept together during or soon after the event that killed them, it is [felt] that this specimen more likely represents an instance of postnatal parental care," the researchers wrote in the study.

Parental care is seen in other animals, including crocodiles and birds, which lived during the time of the dinosaurs. For instance, crocodiles defend their young from predators, and birds protect and feed their young, the researchers said.