<prompt> Child knows his sex by what age?12 months24 months36 months48 months  <response>: Ans. is c i.e., 36 months Important milestones of a 3 years child Rides tricycle Knows his age and sex. Stands momentarily on one foot Repeat a sentence of 6 syllables Draws a circle Has a vocabulary of 250 words Can dress or undress himself completely Counts 3 objects correctly Builds tower of 10 cubes Can withhold and postpone bowel movement 