Wren Barrowright

Wren Barrowright was a halfling and the great granddaughter of Mair Barrowright. She lived in Bedd Mair during the famine of the Nyridda Heartlands.
Wren had heard the family stories about her great grandmother's encounter with a fey, and had inherited the acorn with the golden cap that Lord Kestrin Mithering had gifted her, though Wren didn't know whether to believe the stories or not. But when she and her neighbours began to starve, she decided that she had nothing left to lose and planted the acorn.
A sapling immediately began to sprout from the dessicated earth, and within a few minutes, a huge oak tree stood there. The bark split, and Lord Kestrin came through it, introduced himself, and asked after Mair, a little perturbed to realise that she'd died long ago and someone else had used the acorn. However when Wren introduced herself and requested the boon that he had promised to her great grandmother, he acknowledged the legitimacy of her request. When Wren asked for his help in surviving the famine until the land could support them all again, he agreed, clapped his hands, and a small suirrel ran out of one of the trees and over to the archfey, who spoke to it in Sylvan. It ran through the tree. Seconds later, a host of strange people came trekking through the tree, carrying basket upon basket of fruit, fresh and luscious. Within an hour, there was enough to load several carts, and Lord Kestrin promised to send more the next day. He did so, and for every day until the first successful harvest after the restoration of the Nerys River. The village dried much of the fruit and sent it to the other villages. It was unusually satiating, taking only a few bites to satisfy any appetite. For a long time, Wren was seen as a hero.
But fey help rarely comes without unforeseen consequences. When the villages began to eat regular food again, the residents found that it tasted ashen, and failed to satisfy. They began to grow pale and wane, some even ceasing to eat. They petitioned Wren to call upon Lord Kestrin again, which she did by knocking on the tree in the instructed rhythm, at which point one of his servants appeared, and heard her request. She was told that Lord Kestrin was too busy to meet with her, but her request would be considered. Wren went through the tree with several others to petition the lord personally, but never returned.
Several weeks passed, and the residents lost hope. Then the servant returned. They said that the supplies of fruit could be reinstated, but this time there would something would be needed in trade. Once a year at midsummer, the heartlands must send Lord Kestrin a new servant through the tree for as long as it pleased him.
The residents weren't happy about this, but felt they had little choice. They agreed to the deal.