Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) says that the Messenger of Allah (peace and blessings be upon him) "commanded sadaqat al-fitr on behalf of every young and old, and every free person and slave, among those whom you provide for."
Its chain is not strong, and Allah knows best.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7685