"How many people are there in your family?"

Family. I don't want to go all melodramatic and try to explain the word but here in Viet Nam, the questions always go like this:

1. "What's your name?"

2. "How old are you?"

3. "Are you married?" or "Do you have a boyfriend?"

4. "How many people are there in your family"

Of all the questions they've asked me, I always find the fourth the most difficult. I can always say that I have one older sister but to say that my family consists of only four members stings...
I tried to explain it to a class once, I don't know how much they understood, though. I tried to explain that saying that my family consists of four members sounds like I'm lying, at least to myself. You see, my relatives on my mother side have always been close. True, there have been rifts from time to time among members, but generally, we see each other regularly and include each other in our ups and downs. I remember summers and other vacations spent at my aunts' houses and my cousins who also stayed at our house for days and even months. We have always shuffled in and out of each other's lives. Furthermore, I have friends who I consider as family. No blood ties us, but I can never deny the link or my relationship to them.

The problem is, answering the question this way causes confusion. Either they don't understand enough English or they think that it's a very simple question to answer. Still, I persist in answering that both my parents are alive and together and that I have an older sister... my family, is way bigger and difficult to count.