We study the residential choice of siblings who are altruistic towards their parents. The first-born child’s location choice influences the behavior of the second-born child and can shift some of the burden of providing care for the parents from one child to the other. These strategic...

Altruists and envious people who meet in contests are symbionts. They do better than a population of narrowly rational individuals. If there are only altruists and envious individuals, a particular mixture of altruists and envious individuals is evolutionarily stable.

Altruists and envious people who meet in contests are symbionts. They do better than a population of narrowly rational individuals. If there are only altruists and envious individuals, a particular mixture of altruists and envious individuals is evolutionarily stable.