latchkey kid
child who returns to an empty home after school or a child who is often left at home with no supervision
en-US/ˈlæt͡ʃˌki ˈkɪd/
en-GB/ˈlæt͡ʃkiː ˈkɪd/
child who returns to an empty home after school or a child who is often left at home with no supervision