When is his birthday (in relation to his ordination date)?
Handbook 2 indicates that they must be at least 18. By my math, if he hasn't had his birthday this year (for example, he was born in September), then he's only 17 and too young to be an Elder.
Worse, this makes his ordination to Elder invalid. See "Ordinances That Were Performed before the Appropriate Age" in Handbook 1: 16.1.10 for instruction. If he's already been endowed, someone is going to have to write up some stuff for the First Presidency.
I'd triple check that birth year, because this opens a big can of worms.
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