From the Seforimg blog’s article on bibliophile Rabbi Shmuel Ashkenazi:
Another such story relates to a famous legend about the site where the Beis Hamikdash was built. Told in short, two brothers inherited a field, one brother had a family one did not. At the end of the harvest they divided up the wheat equally. That night the childless brother felt bad for his brother with a large family and said to himself “it’s unfair that while my brother needs more than I, we shared equally”, so he brought over from his pile to his brothers. The other brother thought that since his brother was childless, he should have a larger share of the crop, as consolation, so he added from his share to his brother’s. In the morning each brother realized their piles remained the same and this went on for two more nights. On the third night they met, realized each of their intentions was out of deep consideration for the other and hugged. Numerous people have searched for the early sources for this story. I decided to ask R’ Ashkenazi if he had any material on the subject. He found his file on the story and within was a letter from R’ Yudlov who had been asked by someone in the Education Ministry for the sources on this story. R’ Ashkenazi traced its first appearance in print to 1832 and from there he traced it to other sources.