That alien doesn’t even have a numeral for 4, so it wouldn’t have a word for it either. If it speaks English, uses base 4, and uses the same words we do for numbers, it would sound like this when counting rocks: “One, two, three, ten, eleven, twelve, thirteen, twenty…”. But when it says “twelve”, it means the same thing as when we say “six”.

The joke: In any base X, the Xth number is always the first number to require a second digit. Base 4 goes 1,2,3,10,11,12,13,20,21,etc. Base 7 goes 1,2,3,4,5,6,10,etc.

I don’t know if this has already been suggested (and don’t have time to read all the comments) but penis whittling.

People used to willingly move to the US from other countries. OP could be one of those people.