My father (1923-1993) has one word on his tombstone beneath his name: Steadfast. Mom chose it, and it is appropriate for him.
If I were to choose one word for G, it would be the same. He is constant. Reliable. Giving.
Aidan has already figured this out. He tried to have his first overnight with his big sister at my sister's house. I stayed up, expecting a call, and at 10:15 we got it. He asked to come home, G went and got him, and in the truck he said to his father, "I just can't sleep without you". G lays down with him every night. So this morning G says to me, he may not say I love you yet, but he's mine.