Sex education for children: When and how to begin?

NEW DELHI: Sex stumps us. And if it happens to be a child who wants to know what uncle and aunty are doing in a particularly strange advertisement for a condom, we want to disappear. So how does one talk about sex? When? And most importantly, why?
Is my child old enough to know?
A child is ready when they display signs of curiosity or outrightly ask "uncomfortable" questions.There is no cut-off age. Ideally, one ought to start with the right vocabulary and call vagina and penis by their real names rather than the gazillion codes we invent. And no it's not the bird and bees, it is sex. So, terminology is the key. As the child grows older, discuss where babies come from, tell them no one gets to touch their private parts except the doctor or parents in case of a problem and that too with their consent. "Birds and bees' talks" are not just about debunking the stork story. It is about protecting the children as well. But my child is an innocent angel!
Repeat after me: Sex has nothing to do with innocence. Ignorance and innocence are not the same. An aware child is not a "corrupt" child. They are just more equipped to handle their own curiosity and understand the repercussions.
How do I talk to them?
We are blessed to be living in times when there are a million resources available to initiate the conversation. A personal favourite is the book series by Robie H Harris. I read it a multiple times myself, then read it aloud in front of a mirror till my cheeks stopped going red and then on to reading with kids. A simple first step. Some questions might follow. If you are unable to answer, tell the child you would come back with information. And then keep your word.
We have had the talk. Can I go back into hiding now?
Talking about sex is an ongoing process. Starting with accurate genital nomenclature, one graduates to pregnancy, masturbation, alternate physical expression of love, infatuation and even the pressure that the child at some point might feel to have sex. Yes, I know of teens who get bullied for being virgins. So the conversation has to always remain open.
As parents, we need to destigmatise sex and accept that it is normal for a child to feel curiosity as well sexual urges. It does not reflect on their morality or upbringing. All it does this give the parent an opportunity to provide accurate reliable information rather than the children getting their "facts" from all-knowing friends or porn sites.