A teenager’s bedroom is a treacherous place, and many parents would prefer to remain blissfully ignorant of what goes on in there.

But now a group of mothers are exposing the worst discoveries they have ever made in their children’s rooms via a discussion thread on Mumsnet.

The confessions were prompted by a post by one user starting with the construction: “Today I tidied my teen’s bedroom and found…”

It goes on to list various items of food waste and dirty laundry before concluding with “a Pringle tube full of urine”.

The mother explains that “the lid was on - I reached out to pick it up expecting it to be light... It was heavy, and full of liquid – I opened and sniffed!

“It's just as well he keeps his windows open and heating off. It actually didn't smell too ripe I think it must have been fresh.”

Another mother wrote that her son called for help while bravely cleaning out his own room. She said: “When we peeked under his bed a mouse had made a lovely little home in shredded Twix multipack wrappers.”

“Bottles of urine” emerge as a running theme, leading some despairing mothers to ask why their children cannot make the short journey to the bathroom.

There are stories of more conventional rubbish too – one mother’s “worst” find was “a banana skin under the bed and resulting fruit fly infestation”, while another’s was “a half-eaten rice ball down the side of the bed”.

Apart from a few highlights and the obligatory “used condoms stuck in the bin” and “sanitary towels under the bed”, the general consensus from social media users seems to be that it “could have been worse”.