beard growing

[Mofli]

Hello, I don't know how to say a sentence in English correctly. It should be something like:

His moustache/beard is already growing/sprouting/shooting up/springing up. ???

How would you say it idiomatically when speaking of a teenager?

Thank you very much in advance.

[Mister Micawber]

His beard is / whiskers are already growing/sprouting.
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Native English teacher at Mister Micawber's