"Officially an adult" Daughter looking into getting German Citizenship by Descent

My daughter is now 18 years-old and is looking towards her future (good girl, I'm proud of her for it).

Anyways, she knows that there is German in her bloodline through her mom and wants to know if she is eligible for citizenship through descent, and if she is, needs resources of the how-to variety.

The family involved -

Her grandmother (Born in Germany early 1960s)

Her mother (my ex-wife born in Canada in 1981/un wed mother and father possibly "unknown", need Long Form Birth Certificate to confirm)

My daughter (Born in Canada 2007 to wedded mother (with me))

Everyone is alive and well. Even her great grandma is alive (although has dementia), but was born in Germany.

Grandmother was born in Germany and came to Canada with her parents around 1965. Had a child (mom) in 1981. Apparently, grandmother didn't relinquish citizenship (maybe via Naturalization?) until she was marrying her first husband (maybe around 1985ish).

My daughter wants to know if she is eligible, and if so, how does she begin the process. Specifically, what paperwork is needed.

Hiccups along the way that may require paperwork from what I can gather (from personal research during my failed Italian citizenship pursuit). Both mom and grandmother have been through marriages and divorces, mother was adopted by the first husband.

Any information or guidance would be greatly appreciated as she would like to pursue further education in Europe as a citizen and maybe set down roots in Germany.