The gratitude story "A Glass of Milk" that impacting me from childhood till now is half-real

When I was in elementary school,our Chinese teacher had gave us a exercise book,each page gives a story, we read it and write answers below.The book should be ditched when finished it or graduated and it's been near 10years I couldn't remember the book,the stories and what was I like at that time,but one foreign story's very impressive when I read it from the book,and I still remember the details without ever seen again,

The story I remembered:

A little boy was extremely hungry and thirsty , he past a house for help , a young lady comes out and generously gives him big glass of milk.The boy memorize her kindness in his heart. Time past by that lady got severe illness , it could be cure but when the bill was sent to her ,she's afraid , she finally opened it with fear, it was the amount of milk and the name of the doctor,he was the little boy.

In my memory , the stories on the book was told are all real,and this single one sometimes appearing in my mind,as I knew I have depression , I think about it more ,some people release their little kindness and I could remember it so long.I see some girls as how the young lady was in that little boy's eyes.And as I think , it looks more like fictional: HOW CAN THE DOCTOR RECOGNIZE THE LADY?Name or other things,even though he can get it during the quick help,it was not written...(and lacks other information)It tends to teach people be gratitude.

I search for it and found the story in Chinese, then I search the name of the doctor,it has Wikipedia page,finally I search "Howard Atwood Kelly milk" and found the story.

According to https://www.snopes.com/fact-check/the-milk-of-human-kindness/ (both story above and the real),Kelly was just have a break,the girl's illness was also not serious,Kelly paid it himself same as he did to many other patients that were not rich.

It should be the first "real" story of gratitude that I've heard,fits the quote "滴水之恩，湧泉相報“，I could also see some similar in Chinese history like what Han Xin did, but it's only history though.I would be glad if the story is 100% real.

Even if you are not weak anymore, you still no opportunity to repay some which helped you.It will be great that thus kindness can be everywhere instead of ABUSING,CHEATING...

Thank you all for reading my texts .