It is admirable how you father respected your grandfather although he did not know him well. Also he raised you well, teaching you to respect him. So many families live with lack of harmony these days, hating each other for no reason.
I'd like to let you know we have a community called Family & Friends, which is for this type of topics. Please check it out and join so you can post there next time as OCD is for topics that don't fit in any of the existing community.
Gracias por la observación ....