Communication

My friend has a baby who's about a week older than Dylan. She's a girl and I've heard that girls are more advanced than boys. She blogged that Layla knows over 40 words so I decided to count Dylan's:

36 Signs
Again
Airplane
Alligator
Baby
Ball
Bird
Blanket
Brush teeth
Book
Cold
Come here
Dog
Drink
Eat
Elephant
Fish
Flower
Hat
Help
Horse
Hot
Milk
Monkey
More
Night night/sleep
Off
On
Please
Potty
Rain
Shark
Shoes
Socks
Sun
Up
Water


28 Words/Sounds
Abbey
Alligator “NAP!” (for snap)
Bird “brbrbrbr” (he flips his lips w/ one finger and it makes a noise)
Ble (as in yucky, while he sticks his tongue out and makes a face)
Cat “EE ow” (for meow)
Cow “MMMMmmm” (for moo)
Baby
Ball
Bird “uh uh uh”
Bug
Daddy “dada”
Duck “dika dika dika”
Fish “ees/ah ah ah ooh”
Frog “boe boe boe” (who knows why)
Hot
Lion “AAAAAAAAah” (in a scary roar kind of voice)
Malia “EE-uh”
Mommy “Ommy/mommy”
More “moe”
Nemo “ME-moe”
No
Ouch “aow”
Out
Please “eeeeees/leeeees”
Rosco “Ohhh”
Shark “ay ay ay yay” (while showing his teeth and chomping)
Uh oh
Up

Some words overlap both lists b/c he does a sign and some noise along with it that I will recognize if he does it from the back seat when I'm driving. He recognizes a ton more words than this, but these are what he can produce back to me. Some times he'll spot a word that he knows and will repeat it until I acnowledge him.
So he doesn't speak 40 words yet, but how do you say when he "knows" words? He knows over 40 words that I say. Oh well.