For Josh, for his hypothetical future, "I raised my kids on the command line"
http://lifehacker.com/5974087/i-raised-my-kids-on-the-command-lineand-they-love-it (lifehacker.com)
Though I would hesitate to say at age 5 he can use the past tense "raised", perhaps "I am raising my child to view the command line as the primary means of navigating computers." However, I am a bit surprised at their ability to spell and use all these commands, I suspect the author is glossing over the amount of help the require. Perhaps he is sitting behind them spelling out commands for them? It's a very high level of literacy, not impossible in a 5 year-old, very impobable in a 4 or 5 year old though. This why toddlers and preschoolers do so well with GUIs like the OS on most tablets and smartphones (as mentioned in a previous post) because it is image rather than text based.
In my experience an average-bright child at around age 6, mid-first grade, will move past "reading" for the point of skill development to the point where they have that skill firmly established enough that they can read for learning and other purposes. A very-bright child will get there sooner. But there is a definite point in which the child passes the "reading is the challenge" to "reading is the tool I use to get to the next challenge" level.