I think, maybe, you are taking this a little too seriously.
I know Griff, BCK and Pete pretty well and they are not insinuating anything inappropriate. They are just blowing off steam about the trials of being a father to a daughter be it age 9, 11, 16, 17, 18 or 21.
I know for a fact (because he emailed me) that Griff's daughters were in the midst of a screaming match when he posted. I am guessing that, given where BCK lives (a place I know well as I spent quite some time there), his daughter has had to find some creative way to keep herself occupied which likely has him pulling out his hair. And poor Pete has one who is freshly driving, one in her first years of college and one approaching the end of college and now legal to drink. That he even has the faculty to post is a major accomplishment.
These guys are just making a joke about how they wish piece of mind were as easy as sending their high maintanance kids off for low maintainance plants.
Seriously. Nothing more than that.