Dragon's Horde

In a kingdom, there lives a couple that are said to be the best knights in the land. All around they were called heroes and given the title of nobles. They eventually had a child but did not have plans to slow down at all. One day, there were reports of a dragon in the area so they set out to slay it only for it to be harder than they thought. Never being close to defeat before... they crumbled and pleaded for mercy by any needs necessary. They even mentioned and offered their own son for exchange for their lives when their gold was not enough.