General Septum's Father
Gwinter Septum's grandfather, therefore, and most likely, General Septum's father. Or his stepfather. Or maybe Gwinter was an illegitimate child, like Mariemaya Khushrenada. I'm coming up with too many theories, and I know that no one cares at all, so I say that he's General Septum's Father.

As usual, we don't know too much about this minor character. So, we know that this guy was stationed with Gwinter, his grandson, or step-grandson...Back to the subject. My brain's in 'scandal-overload' mode. ANYWAY! I'm serious now (that's actually a scary thought).

General Septum's father was stationed, along with Gwinter, on Colony D120 when it was targeted by the Barge's beam cannon during a battle between Barge and the Lunar Base. He was prepared to die, but was sorry that his beloved grandson would be going down with him. However, due to Trowa's intervention, the beam cannon missed the colony entirely, so I think it's pretty safe to assume that General Septum's father and Gwinter are still alive.

Not that anyone cares, though.