And because of the life force drained by the Aging Curse, replenishing it would require using life potions that increase life force or hiring wooden profession practitioners of at least Third Order, using the Life Praise skill to slowly restore it.
For the Chen family's more than four hundred people, just the cost of healing them all wouldn't be less than 1 billion Dragon Coins.
The main issue is, with such a large number of people, getting so many potions and the like all at once is not so easy.
If they were to hire someone for help, the debt of gratitude incurred would be substantial; they couldn't avoid bleeding quite a bit in return.
They hadn't been completely wiped out, after all, there were other outsiders present, so they couldn't just take the Fan Family down with them.
"Cough cough, yes, thank you for your grace in sparing our lives!"