LOL, I think he's settling on his own upcoming diaper brand. I think he needs PINK all the way though.
Interesting that the limestone was soaked overnight. I've carved larger pieces of limestone with steel chisels, 5lb mallet, rasps, riflers, files, then down to wet/dry sandpapers to polish. It's the undercutting done in limestone and marble that holds up for centuries in outdoor conditions that I find to be so unusual.
Softer stone can be carved with tools like you've described. It's actually quite soft in comparison to something like quartz or agate. Carving by hand is very close to being a dead skill, sadly.