I think I read his blog back then. Telling about the progress his (then) very young son made. How he didn't install a graphical user interface at first but the kid loved 'sl' (the steam locomotive if you mistype 'ls'), and cowsay and so on. And they had a command-line chat to communicate (or just smash buttons).
For reference about 4 year olds: https://lifehacker.com/i-raised-my-kids-on-the-command-line-and-they-love-it-5974087
I think I read his blog back then. Telling about the progress his (then) very young son made. How he didn't install a graphical user interface at first but the kid loved 'sl' (the steam locomotive if you mistype 'ls'), and cowsay and so on. And they had a command-line chat to communicate (or just smash buttons).