When you’re a kid there are lots of things you believe that aren’t necessarily true.

Most of the time this is down to what your parents have told you (like the police will tell you pull you over if you don’t turn the light off in the back of the car), but other times it’s just what you’ve made up in your head – and nobody has questioned it, so it’s taken as gospel.

In an amusing thread posted on Mumsnet, user @Carryonrunning asked the masses: “What do you remember from your childhood that you now realise you really misunderstood?”

Cue, a hilarious thread of eyebrow-raising confessions… (If you’re a parent reading this, it’s a useful reminder that kids take things very literally.)

“My dad came home from work one day with a hessian sack he’d acquired from somewhere. He then told my mum, ‘I’ve been given the sack’. It took me years to realise that a) he was joking and b) you don’t get given an actual sack when you lose your job.”

– BlossomCat

“As a young child I thought you became an adult at 100 years old. Imagine my shock when someone at primary school told me it was just 18. I had a full on existential crisis when I realised most people don’t even live to 100!”

– Flustration

“My family didn’t have a car, so my main experience of driving when I was really young was my grandad. He only drove us occasionally and from these rare experiences I worked out that the white line in the road was a guideline to keep you straight – a wheel each side of it. When I got to about 8 I began to wonder how cars going in opposite directions could both straddle the centre line without crashing. As I got older I realised my grandad was a really bad driver.”

“In the shop when my mum and dad answered that they didn’t want cash back I always wondered why they turned down free money.”

– EdithGrantham

“I remember leaving primary school one day and I heard the teacher say to a friend’s Mum, ‘It’s the last day tomorrow.’ I must have been about five. I actually thought she meant that it was the last day of the world. I remember laying in bed that evening and worrying and worrying… In the end I went downstairs, crying to my Mum and asked her if it really was the last day of the world the next day.

“To my amazement, she looked at the calendar. I remember thinking, surely the people who make the calendars wouldn’t know when the last day is?! In reality she was just checking that it definitely was the last day of term. She hugged me and explained that the next day was just the last day of term, not Armageddon!”

– Feelinghurt2

“I heard my mum talking on the way home from picking me up at school, to some of her mum friends. She said something like ‘my heart missed a beat’ and from that moment on for YEARS I was afraid that hearts could do this. I worried that my mum’s heart would miss more beats and she would die, or that my heart might miss a beat and something bad would happen. I’d lie in bed listening to my heartbeat and wondering if I’d notice if it missed one…”

– Vroomfondleswaistcoat

“I remember my dad giving the 1 finger salute when driving and me asking my mum what that meant. With a rather frosty look at my dad she said it meant up and over. I then got confused as to why I got into trouble doing it.”

“I thought that the ‘olden days’ really were black and white and there really was no colour – just like the photographs. I thought that at least they had grey and different tones of black and white.”

– Whatthechicken

“I used to think that when you saw a ‘To let’ sign on a building, it was a polite way of saying there’s a public toilet in there.”

– MathsMum3