hello sir/madam, my son is 23 months old. still he has not started to speak. he is able to convey the things to us like he will show us the pitcher when he need water. he will show biscuit box in kitchen when he wants to have it. he follows us when we ask him to switch off the light. he understands things like he does not like to share his chocolates or toys. is it normal or we need to consult the specialist for this.