You can oil it, but I'd try to keep coconut oil well away from his face. People vary a lot in their reactions to it, but a decent number find that it causes acne. BBB? I wouldn't use it on my DH's beard, which would be massively curly if he grew it out, as well as very coarse. It might be OK for some, but I'd think that the average beard would do better with gentle combing (maybe a Tangle Teezer?) and conditioner.
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