Sek was the firstborn son of the Vulcans Tuvok and T'Pel. He had two younger brothers and a younger sister named Asil.
Between 2371 and 2374, Sek went through the pon farr, mated and became the father of a healthy female named T'Meni, who was named after his paternal grandmother. His mother sent a message of this to his father Tuvok, who was trapped in the Delta Quadrant aboard USS Voyager. (VOY: "Hunters")
In 2377, Sek sent a message to his father over a datastream sent to Voyager regarding his studies of music, having found exo-linguistics too theoretical. Unknown to either of them, Bajoran radical Teero Anaydis hid a subliminal message set to Vulcan brainwaves in the message, so that when Tuvok watched the message, it activated a mind control program in his psyche that Teero had implanted years earlier. (VOY: "Repression")