As of 2152, this family consisted of at least thirty-one members, including three wives, each possessing two husbands in addition to Phlox himself, and five of Phlox's children. He missed all of them while serving on Enterprise NX-01, but wouldn't have given up his opportunity to serve there, via the Interspecies Medical Exchange, for anything. (ENT: "A Night in Sickbay")
In the writers' first draft script of "Dear Doctor", Phlox's family was said to be comprised of twenty-seven individuals, including the offspring.
In the writers' first draft script of "Dear Doctor", Phlox's offspring were established as all being fully grown (as of the episode's setting, in 2151) and Phlox himself stated, "I'm quite proud of how most of them turned out."
Having lived through the last war, one of Phlox's grandmothers still harbored prejudice against the Antarans, to the point of forbidding Phlox to visit an arboreal planet near their star system with some friends. Because Antarans had once lived there, she believed it to be unclean years later.
Phlox remembered laying in bed as a child, thinking about her stories, and having nightmares, afraid of an Antaran climbing into his window.
When he grew up, he never told his children her stories, opting for the truth over propaganda. He was proud to say that all of his children, save his son Mettus considered her beliefs to be outdated.
In 2152, Phlox related this story to Hudak, in hopes that the Antaran would accept medical treatment from him. (ENT: "The Breach")
This character was only mentioned in dialogue.
This grandmother and the one above may be the same individual.
Phlox's spouses and their spouses
Along with Phlox, his spouses were each married to two other men each, who were, in turn, married to Feezal and other women. One of Phlox's wives lived in the same town as his eldest son. (ENT: "A Night in Sickbay")
These characters were only mentioned in dialogue.
In the writers' first draft script of "Dear Doctor", Phlox was referred to as having two wives, each of whom had three husbands. Evidently, this later changed to Phlox's wives ultimately being established as instead having two husbands each.