So they could. And?
That you toss this off so lightly, despite the fact that children in these situations have, overall, a horrible life, tells me you agree that it is OK to bring kids into hellish situations, just so long as the parent(sometime s) are "happy.
Nonsense. The numbers say the mother is 62 - and plenty of women at 62 will live to be 82 or 92 or 102. There is no reason that a physically fit woman of 62 can't raise a child and unless you define "young" as 30 or 40, there's no reason to believe that she'll die when the child is young.
And of course, she will be perfectly healthy and not require the poor child to spend his/her entire life supporting the parent.
60 may be the new 50 but 80 is not the new 60.
Poor kid. Instead of living his/her life for him/her self, he/she will live for Mom and Dad. I know every parent wants this.
Selfishness, the Baby Boomer Generation is thy name.