>>> Avoiding eye contact is an unwritten rule on the Tube, but is seems in San Francisco, where this heartwarming photo was taken, commuters are a little more friendly.
A touching photo of a woman helping a young boy tie his tie while travelling in the California city has been widely shared online.
Reddit user Loozar, who captured the moment on camera, explained the woman noticed the boy was struggling and offered to help.
"Kid was desperately trying and failing to do it himself and a fellow passenger asked if he needed help," they posted.
One person responded: "Gotta hand it to people who learn and teach stuff like this that wouldn't necessarily benefit them directly.
"I grew up in a family of women so my sister had to show me how to shave and tie a tie, but she never wore one in her life. I asked her how she learned, to which she responded, 'Had to learn for you'."
The photo has racked up more than 100,000 views and thousands of comments in just 48 hours.
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