Research has shown the young children cannot identify the intimate couple because they don't have prior memory associated with such scenario.
What children or adults with uncorrupted minds will see nine dolphins (if you find it difficult to see 1 dolphin your mind is corrupt) if you couldn't notice any of the dolphins with in three seconds then your mind is indeed corrupt.
in other words...if you have seen naked people you will see the couple, if you haven't seen naked people then you see dolphins.