Question about Six Feet Under: "Nathaniel" on Brenda's Butt

If you’re eagerly awaiting the season premier of this show, as I am, you recall how Nate was surprised to see his name tattooed on Brenda’s backside. It wasn’t him, she asserted, so we have to ask who it was. This being not real life, but a TV serial, it seems appropriate to look around for other characters named Nathaniel. Who could it be? The only other Nathaniel in sight is the spectrally appearing father Nathaniel Sr. Is it possible? Could it be that we’ll discover that Brenda swings both spring and fall-ways, as it were? Is the mysterious Nathaniel none other than than the father?

If you haven’t seen season 1 - SPOILER AHEAD

The “Nathaniel” tattooed just above Brenda’s butt is in reference to the “Nathaniel and Isabel” books that Brenda and her bipolar brother, Billy, read as children. We find this out when Nate sees the “Isabel” tattoo above Billy’s butt and I think Brenda’s parents give Nate (and us) more information about the books when they invite Nate over for dinner without Brenda. The books are also referenced during one of Billy’s “episodes” when he is talking/crying to Brenda.

Billy and Brenda identified with the characters because they were always trying to avoid an evil nurse and getting into adventures. I don’t know if they are real books or not.

Pash