How many?

I was asked how many children I have today. I did not know how to answer. I sat there for what felt like eternity trying to figure out how to answer and trying not to cry. What do I say now?
I could say:
I have three, but one died. This option is awkward and makes for much too serious of a conversation with the casual stranger. And it also opens the door for more questions I don't want to answer.
I have two. This option makes me feel like I would be ignoring his existence, and how he impacted our world. And feels less than honest.
I have three. The next logical response now is to question their ages. At some point, I will have two 17 year olds. It leaves me floundering around searching for words and explanations that don't come.
Some other creative "truth" or running away hysterically?
Its such a strange thing to think about. I believe this is the core of why people who suffer through tragedy & loss feel awkward and vulnerable in public. We no longer belong to that world. We don't know what to say or how to react.
And really, to the person who asked, it probably doesn't matter. I will probably never see them again. I could make up a story, saying I have 14 kids, 3 husbands and a monkey. They would be thoroughly entertained, but the question or the answer wouldn't matter to them. But it matters to me.