A 12-year-old boy asked his mum about her sex life. She answered honestly.

Knowing the moment will come doesn’t make it any easier.

The moment a child starts asking questions about the birds and the bees and S-E-X.

As prepared as anyone thinks they are, the moment is somehow far more mortifying than you ever thought it could be.

At least that’s what one mum shared on parenting forum Mumsnet this week, telling other parents she was caught off guard when her 12-year-old son started asking questions of a fairly personal nature.

“[Am I being unreasonable] to be MORTIFIED at this question?” she asked.

She explained that her son had come into her bedroom saying he had a “weird question” that he wasn’t sure about asking.

The question? “How often do you and dad have sex?”

After double checking that her son did, in fact, want to know the details of his parent’s sex life, she told him that it was “once or twice a week”.

“Even though I tried to seem calm and cool, it felt just really odd. Maybe because I was taken by surprise,” she wrote.

"I am a very modest person and never talk about sex with friends at all, but [my son] has far fewer inhibitions and often mentions things I find embarrassing.

"I would never in a million years have asked that question of my mother! I expect normal 'what is sex' conversations but didn't expect personal questions like that."

Some mothers were appalled that she would even consider answering her son's detailed question.

"I would have told him it wasn't his business," one mum wrote, while another said she was "happy to answer general questions but I don't know about ones so personal".

"Any chance it was a roundabout way of him letting you know that he's well aware you have sex and maybe you need to keep it down?" another suggested.

LISTEN: When is the right time to have 'the talk' with your kids?

Others, however, praised the original poster for the open and honest relationship she clearly has with her son.

"[To be honest] he asked and you felt OK in answering. It's not as if you casually mentioned it to the cashier... or something," one commented.

"I'd say it's a credit to you that he feels comfortable to ask you the question, even if he didn't like the answer!" another said.

Others still said the mother missed a perfect chance to further embarrass her child.

"You missed your opportunity to say, 'We go at it like demented bunny rabbits as soon as you are asleep or when you are out. In fact, we were wondering when you were planning on leaving home permanently. We'd like to install a dungeon'," one person joked.

We can only imagine the poor kid's reaction to that.

Would you make the same call? Let us know in the comments...

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