The mother, along with individuals that may or may not be directly related, conducts cooperative care of young. A reproductive division of labor evolves from sterile castes which often have certain propensities or characteristics associated with helping behavior. There is an overlapping of generations which allows for the older generations of offspring to help related, younger generations.
All ants are eusocial.
They have morphologically distinct workers and queens. In some ants, the workers do not even have ovaries. Other workers can lay male eggs. Many bees are not social at all. Some wasps are eusocial, but many are not.