Posterity comes when the son sticks you in a nursing home, because the new honey doesn't want you around.
And if you don't have anyone to stick you in the nursing home when you need it? I'm reminded of the bumper sticker: "Be nice to your kids, they'll pick your nursing home."
90% of elderly either live independently or are cared for at home by (ahem) family members. Who cares for the childless widow when all her friends are dead and there is no one left alive in the world who even knows her?
Is that the kind of kids you raised?