Habt ihr das gehört?

Can someone help me understand how this sentence can be correctly translated as either ¿Lo habéis oído?, or ¿Lo has oído? The “habt ihr” indicates the speaker is addressing more than one person on a familiar basis - for example, one’s children, or a group of close friends. That matches the first translation with “habéis”. I thought the second translation with “has” would only be used when speaking with one familiar person, in which case the German sentence would be “hast du”. I thought that in Latin American countries where the informal form for plural second person is not used, that they use the formal form “ustedes” instead. Have I misunderstood?