Your brother, Pretesh, is concerned that his 2-year-old daughter's counting ability is well below average. When she counts, his daughter will say, "1, 2, c, door...door balls" when counting the four balls in a picture book

What can you tell Pretesh about the mastery of the principles of counting that will reassure him that his daughter's counting ability is fine?
What will be an ideal response?

A good answer will be similar to the following:
You can reassure your brother that your niece is doing well in the area of counting. Most children begin counting around their second birthday and have mastered the counting principles around age 5 years. Your niece has mastered the one-to-one principle in which she assigns one and only one number name to each object to be counted. She also has mastered the stable-order principle in which the same names for numbers are used in a consistent order. Your niece also seems to understand that the last number name denotes the number of items in the set (the cardinality principle). In other words, your niece's mastery of counting principles is more advanced than most two-year-olds. Tell your brother to relax. Your niece has plenty of time to learn the "real" number names.