Great story about your Dad. I am 40 and my Dad is just like yours. One knee replaced and one needing it. He bought the land (80 acres) that we hunt on here in WI. He does not get out much at all but my son and I (and now Tim) do get out as much as we can. I know he gets just as much if not more from seeing us hunt then when he did. I know this because I know how I felt this year when Matt (hoyt14) got his 7 point and Tim got his first ever with a bow. The memories you created will last you both the rest of your lives. I do hope you have many more hunts with your Dad.