Has Son with Her Stepbrother

As Larry Birkhead's custody hearing looms with grandma Virgie standing largely in the way, TMZ has dug up an interesting family tree -- turns out Virgie liked her stepbrother a whole lot.

Here's the deal: Virgie's mom, Paralee, married a guy named Melvin and had Virgie. In another part of Texas, a guy named George William Tacker got together with this chick named Betty Jo and had a son named David Luther Tacker. Then Paralee and George got married, so Virgie and David became their stepkids. They were all one big happy family -- maybe too happy, because Virgie hooked up with her stepbro to produce David Luther Tacker, Jr.

So, David Sr. is Virgie's stepbrother and her baby daddy. You following so far?