Image copyright Getty Images Image caption There's been a debate in China about children peeing in public

It's a scene familiar to all parents of young children: you're in a busy shopping street and your child decides they just can't hold it in any longer. But one couple's decision to let their child relieve himself has caused a huge schism on Chinese social media.

By now, it seems, the entire Chinese internet is familiar with what happened on a crowded Hong Kong shopping street. A mother holds a nappy while her two-year-old squats and pees. A passerby snaps pictures which then get shared online. Someone else shares a video from the scene, which shows a crowd confronting the boy's parents in a physical scuffle, while the boy's mum argues that she couldn't get her son to the toilet in time. The images have drawn more than one million re-posts on Sina Weibo, China's biggest social network, making it the top trending topic.

Why has this one child's act caused so much upset? Allowing a child under 12 to "obey the call of nature in any public street" is illegal in Hong Kong and could land parents with a 2,000 Hong Kong Dollar ($250; £150) fine. But the online chatter has focused on the fact that this family were tourists from mainland China, rather than being locals. "For Hong Kongers, people might think from time to time that mainlanders are less mannered," says Martin Yip of BBC Chinese. Charmaine Chui, a UK resident who was born in Hong Kong, told BBC Trending she feels "ashamed" to have witnessed mainland tourists peeing in shopping centres and restaurants. "Hong Kong is a beautiful, modern city - what do these people think of it?" she says.

In mainland China, there has also been criticism of the parents' behaviour, including from Chinese state media. But there has also been outrage with Hong Kong residents for being so critical. "It's a two-year-old kid who can't hold it... can't you even be considerate on this?" posted one user. One mainland website commissioned a poll of internet users in which 64% said they can understand the need for children to pee in public in certain situations. An anonymous user of the popular Tianya site was so outraged by the reaction in Hong Kong that he's campaigning to stage a mass protest. "Bring your children to Hong Kong and let them urinate in Hong Kong's streets," he urges his countrymen. "Let's see who will come and take photos."

Reporting by Hannah Moore

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