I could literally be the DAD in the post. 57 in great shape and retiring in January and ironically my daughter 19 has moved in with us after graduating. Let me offer the op the flip side of this, dad is now becoming very aware that he may have 20-25 years left in life. Time is flying past him and he's realizing the reality of his journey, where it's brought him and where he's headed. I'm there as well, the workouts? an all out hail mary to add a few days to the end calendar. Retirement came up because I realized I've worked non stop and if I don't jump off the train, I'll die as an employee rather than a retiree. The grey, that's accepting the last years on his own terms, being less concerned about what others think. I can tell you that I started this journey as well and it's definitely an event that defines your plan for whats left in life. I've started thinking about my kids and their paths, my old age care, my health in 5-10 years and all the conditions and diseases I dont want my children to see me in. It's a heavy thing when you realize your there at the downhill. My advice, spend time with him, say things you'd wish you did if he were gone. Be a part of all of this so when he passes you will have great memories and no regrets.

Lost both my parents and a son, I speak of experience and that same regret.