Is my child gifted?

I hear all the time that my daughter is "so smart" and she just blows me away sometimes, but I don't know if she's just advanced for her age, or if she's really gifted. She is 16 months and says more words than I can count at this point, and knows what every animal I can think of says, uses some 2 word sentances, solves brand new wooden puzzles within minutes, she knows when she sees the colours black, red, blue, green and yellow. She counts 1,2. She knows her body parts. She talks all day and tells her toys when she's putting them in her buckets or baskets. She will sit and look at books (and point out everything in them) for hours. I just wonder because I also have an 18 month old boy who I babysit and he doesn't talk, or have any interest in puzzles, reading or games. I don't know whether to know if he has a learning problem either...
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Child development is as individual as every child is. There are certainly "milestones" and "averages", but there are always children who develop more quickly and some that are slower. At 16 months, your daughter's language would be considered advanced, but is not necessarily unusual. My middle daughter developed language early and spoke in sentences at 14 months. Some children are indeed "gifted", but it would be a bit too soon to reliably use this term with your daughter. Everyone, children and adults alike, have a preferred style of learning. Your daughter's style of cognitive learning is likely active experimentation which lends itself well to learning quickly as a toddler. On the other hand, the 18 month old you care for is likely developing at exactly the speed that is right for his individual needs. He may very well be more of a reflective observer. He is learning, but in a different way than your daughter. It is hard not to do so, but comparing development of children of similar ages is going to usually show some glaring differences. Much goes on in the growth and development of a child in his/her first 5 years of life. If a child speaks early or walks early or knows their alphabet by the time they are 2, it is most likely that by first grade you would not know the difference between her and a child who didn't walk until 18 months or speak until 2 or know his alphabet until kindergarten.
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