老人写信感谢小米之家员工，雷军：很感动，辛苦大家！

Core Points - A Xiaomi store employee received a letter of appreciation from an elderly customer, highlighting the positive customer experience [1] - The letter praised the store's new equipment, pleasant atmosphere, and attentive service, specifically mentioning employee Meng Ziyi for her excellent service quality [2] - Xiaomi's CEO Lei Jun shared the letter on Weibo, expressing gratitude towards all frontline employees for their hard work [2]