The Yellowhill family is not a biological family but a group that any person (even non-halfling, although that is rare indeed) can join and become a part of.
The Yellowhill family is the leader of the families that where left behind in the [first halfling kingdom]] when the renders forced the rest of the families out.
They covered the retreat of the fleeing families and kept the gaze of the renders focused on them. They have been fighting a "last stand" warfare against the renders ever since.
Very military minded and brutal in it's opposition of defectors from the holy war, the Yellowhill family has been "ruling" this part of Midgard with an iron fist, often blatantly ignoring Midgardian law within Midgardian borders and actively fighting a political battle to have the entire hill complex be labelled wild Midgard .
Midgardian lawman often tolerate the infractions of the Yellowhill (like hunting down children that wish to escape being born within the family) but skirmishes between the family and Midgardian guard houses have been common in the past.
The Yellowhill family and it's war are being financed by the Tenluur Family .