My dd is 20 months and doesn't talk, only screams, manages to say yeah, no, dad.
She understands everything.
Our other dd is 5 going on 15, and she talks ALOT. I mean we can't get a word in. We have to tell her she needs to be quiet when we put other dd to bed because her voice echos. She even talks to the TV if no one is there, and talks in her sleep.
When 5yr old wants something she tells us dd2 wants it, or shouts that dd2 wants something.
Do I worry? Is it because dd is talking/asking for her so she doesn't need too?