Answer:
Poseidon is a 20-year-old full-time student who does not support himself.
Step-by-step explanation:
Among the children of Olympians Demeter is a 23 year old student and she supports herself as she is doing a job at grocery store.So her income is not subjected to kiddie tax.
Zeus is 20 years old but he is not a student.
Since Poseidon is a student and his age is 20 years which is below 24 years and he also does not supports himself .So his income will be subjected to kiddie tax.