rodney:
one of the most peculiar lines in The Adventures of Tintin
It shows how times change, because I would have assumed that this was such a common expression that it wouldn't have merited a second look! Presumably it has fallen out of fashion?
It will certainly be found in all sorts of writing; having the Captain say it wasn't because it was a nautical thing, it's just an expression which means "someone young".
The etymology of the expression is (as for so many words and phrases) uncertain.
It could be a reference to young children being a
chip off the old block, a "shaving" of their parents - and might explain why some people use it for children regardless of gender.
Others connect it to
shaving, and make it male (although as it can be used for very young children, that seems a bit of a back-formation).
A third (and in some ways the most convincing) origin is that it comes from the Romany
chava - which is also a word for a young boy.
This latter word is also said to be the origin of the British slang word "chav", now mostly used as a term of abuse for someone thought to be poor and lacking in taste.
It's unlikely to be a word-for-word transcription of the French, but I imagine that there is a similar expression there too.
