As kids both were victims of the cruel world and bad parenting. : r/ShingekiNoKyojin

Grisha Jaeger (Anime), Attack on Titan Wiki

Attack on Titan That Day (TV Episode 2019) - IMDb

Why did Eren allow grisha to see zeke,was it simply out of kindness or was there something more to it? : r/ANRime

Grisha Yeager, My Little Pony w/ Reiner and Bertholdt Wiki

Eren touching Grisha during the Stand Father scene : r/ANRime

Attack on titan: Why did Grisha Yegar not reveal the truth of the world to the people inside the walls? - Quora

In Attack on Titan, when Eren asked the trainee squad teacher about his father, he said it has been 20 years since then and Eren has been a titan shifter for 5

Why did Eren not inherit his father's memories? - Quora

Grisha Jäger, Wiki

If Grisha has already seen the future of Eren destroying the world, why did he give Eren the power of both the Attack Titan and the Founding Titan? - Quora