Alex doesn't have a grandson.
62 grandsons
There isn't one for 'grandson' or 'granddaughter' specifically, but 'mokopuna' in maori means grandchild.
Charles, Lothiar, and Louis are Charlemange's grandsons but his son's name is unknown.
The plural possessive form of "grandson" is "grandsons'".
Alex Cord's birth name is Alex Viespi.
Alex Sabga's birth name is Alex Sabga-Brady.
Alex Santella's birth name is Alex Thomas Santella.
Alex Shibutani's birth name is Alex Hideo Shibutani.
Alex Hoover's birth name is Alex Janie Hoover.
Alex Dillard's birth name is James Alex Dillard.
Alex Angarita's birth name is Alex Augusto Angarita.
Alex Datcher's birth name is Cynthia Alex Datcher.