While this know-all-ness bodes well at school, at home it's a bloody nightmare. Mainly because he thinks I don't know anything. He thinks I'm daft. No matter how many times I tell him that I can read, that I have actually WRITTEN BOOKS – no matter how many times I say I have a job, he just thinks I'm that woman with the big bum and baggy pyjama bottoms who cleans, cooks and sweeps the floor.
His dad, on the other hand, is the font of all knowledge. If he looked up to him any more he'd get a crick in his neck. To top it off, since I left my bag in a taxi THREE YEARS AGO, he has me down as an absent-minded flake, who will forget where I live and endanger all our lives with my stupidity.
To be a mum is to be undermined on a daily basis. (Or should that be Mumdermined?) They have no interest whatsoever in imagining you in a role beyond your assigned motherly duties. If my husband uses the laptop (to buy trainers on eBay, usually) then 'Daddy is doing work.'
When I'm on the laptop, actually working, 10 sticky fingers immediately redirect it to the CBBC website. No wonder a lot of women find parenting so frustrating.
To my son, I'm essentially a pair of comfy arms, a soothing/scary voice and the woman who puts too many peas on his plate. And it seems I'm not alone in having to deal with my child's inability to see me as anything more than a dustpan and brush in a wig.
"My daughter told her nursery teacher that 'Daddy goes to work – Mummy goes to Waitrose, " says one disgruntled mum.
"When my son was at nursery, he wrote that I was helpful 'like a servant' - on my Mother's Day card," says Wendy.
"My five-year-old gave me the broom so I wouldn't bother him on the iPad. Another time he told me 'cleaning was my job'. I'm on strike, now," adds Michelle.
"I'm the cook and the chauffeur and groom but my main role is to be totally uncool!" says Oonagh.
But why are our kids so down on us in our day-to-day lives? Why do they see us as simply dogsbodies? It's nothing to do with upbringing or discipline. My kid loves me to bits and (usually) does what he's told.
He thinks I'm wonderful – but he doesn't think I DO anything.
So why do so many children go in for this form of Mumdermining? Are they simply used to seeing us in a certain light, as the provider of their basic needs? Or – paging Dr Freud – is their belittling of us to do with a need to get away from the maternal clutches and forge their own path in life?
"My daughter spent a day with me at work when she was seven and I was a partner in a law firm. She saw people ask me questions and said: 'Why on earth are they asking you?' and fell about laughing," says Lucia.
"I think my kids are just not used to seeing me in that role. At home I'm mum: cooking cakes, taking them out and reading stories - I have to be a different character at work."
And boy, mothers are multi-faceted characters. "Women's lives and the roles they play are too complex for children," says my friend Stephen. "Even grown men can't work you out."
True enough. And maybe kids need you to be 'Just Mum' - a nice, safe jumping off point for the scary world, a person who is always there. If I'm honest I sometimes treat my own mum with a little bit of arms-length snootiness and eye-rolling if she gets things wrong, even though she's the first person I turn to when I have a problem.
But to be on the receiving end of it is terrible for the self-esteem.
Children, basically, have got to stop treating us like divvies. They need to start giving us a break. We are noble goddesses. We multi-task and work and hold everything together. OK, so it's probably too much to ask them to be grateful, but a little bit of encouragement wouldn't go amiss.
And kids: there are plenty of ways you show their appreciation of our hard work. Get your own cereal, tidy your own room, go out and get a paper round, or sell that Star Wars Lego on eBay and buy mummy a trip to the Maldives. Tell your friends we go to work and have friends of our own and we look really pretty. Easy!
Otherwise, you might find that we'll suspend service until we're truly recognised for the well-rounded, exciting, knowledgeable people we are.
And who's going to roll your socks into a ball then, eh? Because we're DEFINITELY the only people in the house who know how to do that...
What's the biggest praise-not-praise your child has said to you or about you?
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