Zhao Dashan was publicly humiliated by his son Zhao An and daughter-in-law Li Ran for buying a four-yuan pack of cigarettes on his late wife Sufen's birthday, so he angrily moved back to the old family home in Locust Tree Lane. The couple soon discovered the truth: the old man had spent his life savings to buy the house and used his entire pension to pay off the mortgage and support the family, leaving them consumed with guilt. When their granddaughter Xinxin suddenly fell ill with leukemia, the old man resolutely sold the house to save her, fighting off relatives who came to seize the assets. In the end, Xinxin recovered, and the old man returned to the old home to live out his remaining years in peace. His children grew up and came to their senses, each family finding its own warmth and contentment—a life of modest fulfillment at last.