Miscommunication- different languages?

Yesterday I (Jess) had a monster headache so Doug took the boys out for a stroller ride while I rested. While he was pushing them, he said they talked for a long time, back and forth, nearly 15 minutes. Finally, Ethan sat back in his side of the stroller and looked frustrated and said, "Baxter, I can't understand a word you're saying!"

Maybe not a cross-cultural misunderstanding, but definitely a language barrier between our 2 sons!