My DD is 16 months old and can't say anything she sometimes mumbles mama but it isn't aimed at me and if I say for example "shall we go to grandma's?" She might respond with a "ye" but doesn't necessarily mean yes she can get her point across by pointing and making aaaa AAA AAA noises to something she wants. She can also follow quite complex instructions like " right pick your dummy up get your bottle let's go to bed" and she does it all and goes upstairs or tidy your toys away or if we're at someone's house and I say okay let's go now say bye she will say bye and go to the front door. She can also walk and if you ask where's your tummy or your nose she points to them but just no words...is this abnormal? Should I be worried?