I say, and with God's success: If the insane person is wealthy, Fitr charity is obligatory on him; and it is given by the guardian from his wealth; because sanity is not a condition for the obligation of charity; it is not purely an act of worship but has the meaning of support, unlike zakat, which is purely an act of worship. However, if the insane person is poor, it is obligatory on the father. Refer to: Al-Badai 2: 70, and God knows best.