The post was titled "Neglect or just c**p parenting?" and the mum said she was increasingly worried the child was being neglected.
One parent said the poster was overreacting, and revealed they left their five year old children at home alone.
"I used to leave my five year old for about 10 mins to do an errand," Enb76 wrote.
"I'm not a neglectful parent. I would never have left her asleep to wake up on her own. I'd tell her where I was going and how long I'd be...she's a sensible child."
However to date the topic has proven controversial, with more than 380 comments in response to the original question.
Some parents, perhaps remembering the famous film Home Alone, said it was completely unacceptable.
"Five is way too young to leave a child alone," PerpendicularVincent said. "At that age, they don't have the common sense to avoid danger. Eg, lighting matches, putting on the oven etc. No errand is so important that it's worth the risk."
Another user, who is presumably in the police, agreed.
"I've arrested someone for child neglect when she went to the hairdressers and the child had got out and was found walking along a dual carriageway. It's cool though because it was 'just a trim'," they wrote.