Second word?

One thing (of the infinite) things that has always confused me is what actually qualifies as a "word" when it comes from a baby. I mean, no one ever really says that "mama" and "dada" were their kid's first words, but that is usually what kids say first. Is it the first word they say after that? Or the first word that someone other than their parents can understand? I don't know. But, anyway. Will's first word aside from mama and dada was definitely "dog." He says it pretty clearly, so I'm going with it. His second "word" has popped up in the last couple weeks and it's "Kaaaa." So, here's where it gets dicey because it's not really a word, but it does have meaning to him, and that meaning is definitely "Kate." He loves to say it loudly to get her attention and she loves to tell me that Will likes saying her name more than anyone else's. Which is probably true. Whether it's truly his second word or not, it's exciting because it means we're one step closer to him talking! (Yes, I use the exclamation point intentionally. I'm excited to converse with him, even though I know it means hearing a lot of "NO!" and "MINE!!")