What could your sons say at 1.3 years old? My mom keeps worrying that my son isn't talking much, say…

What could your sons say at 1.3 years old? My mom keeps worrying that my son isn't talking much, saying he doesn't say 'mama' or 'dada' and so on. But for him, it comes in waves: sometimes he talks a lot, then he quiets down. He can chatter a lot in his own language and imitate. For example, he imitates how a car sounds. He even repeats after me how animals talk, but he's not always interested in that.