Ciro says

Oh Yes, he is an American boy.
Now that he finally starts to pick up words much easier than before (2 or 3 new words every day, and if you ask him to say something, he would most possibly agree to mimic the sound-although not perfect-even if he might not know what it means), he is saying English words 90% of the time.

Words that he started to say most recently:

Ciro (he would sometimes correct us when we call him xixi now)
Jeep
Bus
Chu-chu Train
People (he could point to others and himself when saying so)
Bang
Pat pat pat (to fire Rocket)
poo-poo
yummy yummy
......