Here's a few of the definitions I found:
- An unbranded range animal (especially a stray calf); belongs to the first person who puts a brand on it.
- An unbranded range animal (calf, cow, or steer), especially an unbranded calf that has become separated from its mother, traditionally considered the property of the first person who brands it.
So it seems maybe, by this definition, maybe Sarah and John actually ARE mavericks... who will belong to the first person who puts their brand on them... Pretty scary.