It is great that you dive with your Dad. The coolest!
My daugther was swimming at about a year old. She started snorkeling when she was four years old.
When she had career day at her elementary school, she invited me to talk about being a scuba instructor. Instead, I spent most of the time showing the kids pictures of her free diving in the Florida Keys. She was the coolest kid in the class that day!
When she turned twelve, she told me that she wanted to get certified to scuba. I think that, in most cases, teaching a family member is not the best way to go. So I had a friend at a scuba shop become her instructor. After her certification, we dove together a few times.
Sadly, as my daughter became a full-fledged teenager, she decided to stop diving--she is now fifteen. I really miss our dives together, because our dive trips were always more than just diving; it was our special time together. We would talk about life and things on the hour long ride back and forth to the Keys or before and after the dives.
Though I want her to be happy in life, which is most important, I have to admit that a little bit of selfishness inside of me is waiting for the day when she calls me to say that she wants to start diving again. I still keep her Junior Scuba Diver card and her DAN insurance card right next to mine in my safety kit--just in case.
You will remember your dives with your Dad forever, and I know that he will never forget these times, either.