<prompt> Answer this question truthfullyWhat is the typical age at which a child will begin to walk, develop object permanence, say two-word phrases including papa or mama and one other word, and experience separation anxiety?  <response>: <reason> The typical age at which a child will begin to walk, develop object permanence, say two-word phrases including papa or mama and one other word, and experience separation anxiety is around 12 months old. 