The box of jade is all his family savings, prepared for five years later. If Susu marries him, it will be her betrothal gift; if Susu marries another, it will be her dowry. He only asks the Old Madam to give him a chance.
The letter also mentioned some miscellaneous things, and the Old Madam could sense some of Hong Sheng's thoughts. Susu has been making clothes for him for years, and gradually some complex feelings developed. Later, they met again, and to say he's not fond of her would be a lie. But what truly made Hong Sheng determined was the thoughtful gifts Susu prepared for him on behalf of the Old Madam before he left, considering every aspect for him.
The reason for his rapid promotion is undoubtedly partly due to those gifts. Though Prince Ke arranged for him to join the Northwest Army, the prince's name isn't particularly useful in the military!
