Q: Who has to pay zakat al-fitr?
A: Zakat al-Fitr is obligatory upon every Muslim to pay for themselves and on behalf of every Muslim under their care (so long as it is in addition to their obligatory spending of both the night and day of ʿEid, what is required of living quarters, servants, transports, books of knowledge needed to read and master, and daily clothing, etc.). It is recommended to pay zakat on behalf of a child in the womb.
Source: Bidayat al-Abid