Hello everyone, thanks for sharing your thoughts on this. We don't have a blanket rule against under 18s posting here; after all, there are parents who are under 18, too. We also know that lots of younger people appreciate the pool of wisdom and advice here.
In this case, we'd received a lot of reports about the thread and we did share people's concerns that Mumsnet might not be the most appropriate, or safe, place for a thread like that. Of course, we can't always know that someone underage is posting, but when we do, we do need to check things out and make sure that it's safe for them to do so. Posters who disclose that they are children can also add a level of vulnerability that we do need to weigh up here on an extremely busy, public forum.
Mumsnet is primarily a site for adults, and if we feel as though a child might not be using the site in a way that's safe for them, and for other Mumsnetters, then we would suspend the account. It is a bit of a case by case thing which is why we appreciate reports so much. We'd never want to cut anyone off from support- that's not what we're about- but sometimes Mumsnet might not be the best place for it.
We also have no reason the believe the OP wasn't genuine, and FWIW, CoedynSbageti has been with us for years and can confirm that what she claims checks out.
Hope this helps clarify things a little.