Toddler Language Awareness

I basically assume that ML (2) doesn't make much distinction between German and English since he mixes freely right now - he'll say "You're krank" and "I go draussen". Pretty common stuff for a bilingual this age. Of course I address him in German, even when we're out in public and we've gotten some funny looks lately from the kids in NJ's karate class. So it was a lot of fun when Emma, who is 8, asked for me to tell her some phrases in German. She then repeated them to ML - "Setz dich hin", "Komm her", "Werf den Ball." He was delighted! He thought it was hysterical. So I guess he really does know the difference since he didn't expect Emma to be speaking German to him.