she is just fine! your freind's son *might* be advanced or gifted... but that could be a fluke. My daughter can say about 20 different animal sounds and names, knows 4-5 letters of the alphabet (out of order) and can count to two, or three on occasion. She can recognize several colors... but that depends on her mood more than anything. She has a large vocabulary (we lost count long ago).
at this age kids will each have their interests. Whatever INTERESTS them will be what they pick up and memorize the most. This could be based on whatever their parents react most positively to! a kid who sings the ABC song every day naturally will pick up the ABC's faster than a kid who doesn't.
Also, don't ignore the little achievements in OTHER areas that can show development. My daughter can do a real pull-up, somersaults and a lot of activities that take dexterity and body awareness! She can handle staircases by herself with ease, turn doorknobs and locks and even handle the TV remote and xbox remote (and know what she is doing)! She can make towers of blocks and can carry out complex patterns during pretend play. (she can feed, clean up, dress and put baby to bed in order, and then say "good morning baby" and do it all over again!) Intelligence is A LOT more than ABC's and 123's! A lot of kids who are "slower" in one type of intelligence are advanced in others!
More than anything, make sure your child is PROGRESSING. It doesn't matter how fast they are learning in each category of development, just that they ARE learning. if you are worried about a specific area, focus on it for a few weeks and chances are your daughter will catch right up! Don't forget that doing is a huge part of learning, so get out there and try to DO things with her!
I bet if you sit down and really think about all of the incredible things your toddler really is able to do, you'll be surprised. A friend of mine was certain her daughter had a speech delay! I sat down on the floor next to her daughter and said, "no she talks just fine... she is just whispering! tell her to be louder!" The kids with disabilities usually really stop progressing at one point or another. OR they even start regressing. If you feel this is the case... sure, call a doctor- but just because she can do all the stuff another kid can doesn't mean she is slow- it just means she is an individual!!!
Good Job Mama! (By the way, my daughter is 27 months (2yrs 3 mo). Her most recent achievement- full sentences and deliberate sneakiness- eek!)
-M.