Mostly he says Appa a lot (as in Korean for "dad" rather than giant air bison, as far as we can tell), and occasionally says Eomma ("mom"). That's about the extent of his vocabulary other than repeating da-da-da-da ma-ma-ma-ma and strings of nonsense syllables that mimic the rhythm of speech. He's slow compared to his cohorts, I'm told, but both Mark and I were slow-to-talk babies so it was inevitable.