Passengers wait to board trains at Guiyang Railway Station in Guiyang, capital of southwest China's Guizhou Province, Feb. 3, 2017. China's railways braced for post-holiday travel rush, with travelers returning to work after the week-long Lunar New Year celebration. (Xinhua/Liu Xu)
On Valentine's Day this year, it was not a love letter but a handful of "leave request" letters that touched the hearts of Chinese netizens.
The letters were written by a couple who both work as train drivers in central China. These were not their normal leave request letters, however, all of the letters were written to the couple's five-year-old daughter Chen Yutong.
"Dear sweetie, Spring Festival is just about to start, and with it comes the annual travel rush. Daddy and mummy must work overtime, so we can't be with you for the holiday," says one letter penned by the girl's mother Xiao Sanying.
The letter was signed off with: "We would like to request leave. I hope we get your approval. Love you, your daddy and mummy."
Chinese netizens were moved that the couple wrote such letters to a child.
"I cried after reading the story. I, too, have to leave my daughter for work in a month," wrote one netizen.
Being an employee of China's massive railway system can be exhausting. Even more so during the Spring Festival travel rush, or "Chunyun."
It has been estimated that around 356 million train trips would be made during the 40-day Chunyun period that will end on Feb. 21. The city of Wuhan, where Chen's parents work, is one of the country's busiest train hubs.
Drivers work rotating three-day shifts to ensure the system runs smoothly. It may not be a problem if only one works in the system, but in a family with two train drivers, time together is a rare treat.
The couple missed their daughter's birthday, school events and holidays. Chen's main carers are her grandparents.
Racked with guilt, the young couple started to write letters requesting their daughter's permission to take "family leave." Since their first letter, which they wrote on the last day of 2014, 16 more have followed.
Chen's mother, Xiao, explained that the couple started writing letters because there was one day when she could not attend her daughter's kindergarten sports day.
"She was so sad. But when we were home, I drafted a letter and read it to her. She seemed to understand and came over to hug me and kiss me," Xiao said.
Some netizens applauded the couple's work ethics, linking it to the selfless spirit of the older generation who toiled selflessly to help lift the country out of poverty. As Chinese have become better off, they have more free time and are able to strike a better work-life balance.
Chen Gang, the girl's father, often underscored the point of sacrifice and job dedication in the letters he penned.
"There are so many grandpas, grandmas, uncles, aunts, brothers and sisters who take the train to be with their families," Chen said. "My daughter, you need to understand that it is the responsibility of your father and mother to make sure these people get home safe for the New Year holiday."
The couple's story is no isolated case, many railway workers today still sacrifice time with their family to work.
Chen said the letters were also a way to show their daughter how important it was to help others.
"We want her to understand that her parents were absent because they were helping people," he said.
Despite all this, Chen and Xiao are not without regrets.
Their absences have meant that they have missed out on being there for their daughter when she needed them.
And while it is reassuring that the child's grandparents are there for her, it means that their daughter is closer to them than her own parents.
"One day I went to pick her up from kindergarten and said she wanted her grandma, not me," Xiao said.