Household baptism

Blumenfeld again, quoting Wayne Meeks: “The household, especially in Romans times, develops into a vast and complex system of inner and outer connections of allegiances and obligation, a ‘network of relationships, both internal – kinship, clientela , subordination – and external: ties of friendship and perhaps of occupation.’” Blumenfeld suggests that ultimately “the oikos effectively substitutes for the polis in meaning and extension.”

So: Who was baptized when “households” were baptized?