By now, we're pretty familiar with metal songs becoming lullabies, but this proud parent went one step further than just popping in a CD to lull his baby to sleep. He probably didn't expect what happened when he took to his acoustic guitar to play Metallica's 'Nothing Else Matters.'

If you listen closely, it appears as if the baby is cooing a loose representation of the lyrical phrasing from the Metallica hit! Where 'Enter Sandman' seemed like the obvious lullaby choice, this dad looked past the obvious tune and broke out a song that turned out to yield even better results.

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