The ATC takes a secondary set of skills to lower someone [while belaying] from a long distance from above.” Both devices are capable of accommodating high-risk situations, but the GriGri is more likely to switch between uses at a faster rate, which can be essential in extreme or life-or-death situations.

Rappelling with the GRIGRI can be done on EN 892 dynamic or EN 1891 low stretch rope of a compatible diameter indicated on the device. There are several ways to set up the rope for rappelling: they are described in the technical tip, Multi-pitch rappelling with a single rope.

: a talisman, amulet, voodoo charm, spell, or incantation believed capable of warding off evil and bringing good luck to oneself or of bringing misfortune to another.

Daughter is using a Grigri as a self-belay device. This is expressly discouraged by Petzl, the manufacturer, on this page titled Self Belaying is Prohibited. That's pretty damning. As the page admits, some people do use a Grigri for self-belays, but it's not ideal and potentially dangerous.