Well, if you're talking daddy ball so that junior can be the shortstop and pitcher that should end at around age 5 or 6.
I guess technically I'm doing daddy ball for a 13/14 year old youth team, but I think I'm doing it for some of the right reasons. Son has been on various teams which I have helped with, but I never felt he was getting any kind of quality instruction, productive practices, etc. One head coach was so wrapped up in himself he called the kids together in the middle of the field during a game and ripped them a new one for messing up a rundown (which had not been practiced at all that season). I've always said if you don't like the way something is then do something about it. So here I am playing head coach.
One of my biggest gripes is seeing coaches waste time at practice by being unprepared, having 9 kids stand around in the field doing nothing while a batter at the plate attempts to hit pitches that are over his head, or just running the same drills day after day. So I spend an hour or two a couple of nights before every practice and type up a practice plan and post it on our website so the kids can get ready for what we'll work on. I video pitching and batting and post slow motion clips on the website so the kids can see what they need to work on. I want the ones who strive to play high school ball to be ready for it.
My son is a pretty good kid and so on, but right off the bat he bugged me to put him at SS. Well, there are two kids on the team who I feel are better at SS than my son, so no SS. Son has caught for quite a while and is good at it, so right now he catches, plays 2nd, and plays outfield. I'd like to do something special for the catchers from time to time because sometimes they do take a beating in games (son certainly has), but since the coaches kid is a catcher none of them get any special treatment.
I don't pretend to know everything about baseball, there are certainly many coaches that know more than me. I study DVD's and books to stay ahead of the kids, and of course glean information from a few good web sites.
That's where I'm at with daddy-ball at the moment. So far my relationship with my son has stayed on a pretty even keel while being his coach. It's not always perfect, but we do pretty well. In a way it's an advantage because we communicate really well and as a catcher he picks up on a lot of stuff that the other catchers wouldn't think to tell me (Tom's changeup is awesome today; Joe's starting to lose his stuff; the ump's calling strikes off the outside corner, etc.)