My former FIL was in ICU, non responsive for a couple of days. I brought my younger daughter (then age 7) and niece (then age 9) in to say their goodbyes. They both wanted to hold his hands, I told them it was ok to do so. As soon as they took his hands and said “Hi Grumples” he opened his eyes just a little, said “My Annie, my Sweetie (his nicknames for them), I love you.” 
He closed his eyes and did not open them again or respond to anything for the next two days until he passed. 
He loved his grandkids more than anything. He had the chance to prove that one last time. Just like your dad did.