How does finding the jade peony at the end of the story help Sek-lung with his grief?

At the dawn of the 20th century, the peony was declared to be the National Flower of China. Jade is the gemstone most associated with Chinese cultural artifacts. Together, the combination of peony and jade make for perhaps the quintessential symbol of Chinese history and heritage. That the titular symbol is most strongly associated with the grandmother fighting against assimilation into Canadian society, it takes on even greater meaning. The Jade Peony provides a tangible connection with his late grandmother.