Though the Planeteers are only teenagers, their parents and families are rarely mentioned. This page gives a brief rundown on what the audience is able to learn about their families through canon evidence.
Kwame briefly mentions his mother in the episode A Mine is a Terrible Thing to Waste Part II, stating that she was ill and he had taken on the duty to collect firewood. No mention is ever given to his father, and he does not state how serious the illness was regarding his mother's health. It is possible Kwame has two healthy parents back in Africa, but it is also as likely he has none. Kwame never mentions any other family, indicating that he is an only child. It is possible Kwame's mother is briefly seen in the episode A Mine is a Terrible Thing to Waste Part II as he stands and waves back towards his village. A woman wearing a purple dress waves back to him, though she is not shown very clearly.
Wheeler's parents are still alive and married in Brooklyn, though it is strongly hinted that Wheeler was a teenage runaway. In the episodes A Mine is a Terrible Thing to Waste Part II and Talkin' Trash, it becomes evident that Wheeler's father is an alcoholic. At the very least, he was verbally abusive towards Wheeler, and would often send him on bottle-runs to get him more alcohol. When Wheeler returned emtpy-handed, his father would hurl abuse at him. Wheeler's mother appeared passive to this environment, though he seems to be on good terms with her when he visits his parents in the episode Talkin' Trash. Wheeler's father falls ill, which Wheeler seems unsurprised by.
Wheeler's father is shown as strong, muscular man in A Mine is a Terrible Thing to Waste Part II. He has brown hair and dark eyes and wears a white singlet and blue jeans. In the episode Talkin' Trash, it is evident that his lifetime of drinking has worn on his health. He has aged rapidly and his physical build has changed dramatically. Given that Wheeler is approximately ten or twelve in the flashback during A Mine is a Terrible Thing to Waste Part II, and around seventeen when he is summoned to the Planeteers, the decline in his father's health appears to happen very rapidly. At the end of the episode Talkin' Trash, Wheeler and his father have made tentative steps towards a reconciliation, mostly due to Trish. It is never stated whether or not Wheeler's father dies of his addiction to alcohol, or if he manages to turn his life around and regain his health. The latter could certainly be possible, given that his attitude appears to have changed at the end of Talkin' Trash.
Neither of Wheeler's parents are ever named in canon. Fandom has sought confirmation that Wheeler's father's name was "Nick", but this is unable to be supported via any of the episodes. It does appear that Wheeler is the family's surname, however.
Linka's mother is never mentioned at all, though her father is seen at one point during a flashback in the episode A Mine is a Terrible Thing to Waste Part II. The main person in the parental role for Linka, however, is her grandmother. Grandmother appears to have ill health at times - Linka even quits being a Planeteer in order to return to her hometown and nurse her grandmother back to health in the episode Missing Linka. Linka refers to her grandmother as "Grandma". Linka's father worked in the mines in her hometown. Linka and her grandmother raised the canaries which the miners would take down into the mine in order to detect dangerous gasses. Her father would bring the dead birds home, acknowledging that it broke Linka's heart every time. (This is seen in the episode A Mine is a Terrible Thing to Waste Part II). Linka is the only Planeteer with a sibling - her older brother, Mishka.
Gi's parents are marine biologists. Gi appears to have had the most conventional family upbringing - two loving parents who supported her dreams of marine biology and passed on their own knowledge. It is not explicitly stated, but canon supports the idea that Gi's parents are still alive and well somewhere in Asia. Gi's parents appear in the episode A Mine is a Terrible Thing to Waste Part II, during Gi's flashback. They are shown in their research lab. Both are wearing white lab jackets. Gi's father wears glasses with thick black frames.
Ma-Ti reveals in the episode A Mine is a Terrible Thing to Waste Part I that he is an orphan. His parents were killed during periods of unrest between developers and the indiginous people of the forest where Ma-Ti grew up. Ma-Ti was then raised by the Shaman, whom he calls "Grandfather". Ma-Ti has his father's necklace, which was made by Ma-Ti's mother. Ma-Ti's father's name was Chico. His mother's name is never revealed.