Kate hasn't actually said those words (or much of any words--still waiting!) but as her "receptive vocabulary" grows, we're finding that she can respond to requests more and more often. For example:
"Kate, go get your cup."
"Let's find your shoes."
"Can you put the spoon in the dishwasher?"
"Come get the book and take it to Ms. Julie."
We see evidence of her understanding more and more as she follows directions and responds to the things we say. It's pretty cool.
I can point to a toy that has rolled into the kitchen from the family room and say "Go get the yellow ball," and she'll turn around to look, and then go get it. I have to admit, the most impressive part of that action to me is that she understands to look where the finger is pointing, not at the finger itself. No dog or cat I've ever known has grasped that concept, but obviously, humans are a bit more advanced than that :0)
She babbles quite a bit, but we're still waiting for the big "language explosion" we're sure is right around the corner. We talk, read, and sing a lot, so I know she's well-exposed to vocabulary, yet "Mama" and "Da" are still her only words, and even those aren't that reliable. ("Baba" has faded away now that we're using a sippy cup.) I'm so curious what her first "real" words will be. Maybe "mow-mow" or "cup"?
She does make the noise "a-la" a lot, and I'd like to think that's the start of "I love you." Goodness knows those are the words she hears most in a day! That and "you're so cute," but that Y-sound might be a difficult one to master.