Colton Haynes 4 Days After Engagement ... Already Talking Kids!!!

3/17/2017 12:40 AM PDT

Colton Haynes is on the fast-track ... a quickie wedding followed real quick by some bambinos. 

The "Teen Wolf" star was all smiles at LAX Thursday after getting engaged to Jeff Leatham in Cabo.  

He knows at least one song they'll play at the wedding.  

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