Meri , Robyn , and Christine was all raised in polygamist families , but Janelle was not . Although Christine 's mother left the faith she still support them . Months before the marriage of Janelle and Kody , however , Janelle 's mother entered into a polygamist marriage with Kody 's father . The Brown family belong to the Apostolic United Brethren ( AUB . ) For years before the series , the family kept their polygamist lifestyle what they called a " quasi @-@ secret " .