Though the author calls it something different, what she is talking about really is just discipleship.
Yet while having friends of the same age is normal and natural, we miss something special when we don’t have any friends who are of different ages than us, particularly in Christian community. Christians share a bond and identity that trumps everything else — job, race, and most definitely age. If there’s no longer Jew nor Greek, slave nor free, male nor female, there should be neither old nor young
We get in trouble as a church when we forget that the kids, parents, teens, or seniors are all just disciples needing to be discipled and to disciple others.