Spoiler Alert, click show to read: 
How come J.K. suddenly decided that Ron could speak Parseltongue? I mean, come on.
Spoiler Alert, click show to read: 
Yeah, that did seem a bit odd. The ironic thing was that they didn't even need the basilisk fang anyway, as that mystical fire took care of the ravenclaw horcrux. I suppose there was still the need for them to have a way of destroying it, barring that odd coincidence.