It’s just like the Amish, people with an old fashioned lifestyle. It was common 100 years or so ago for people to get married at 14, pedophilia is with pre-pubescent children.
FLDS are NOTHING like the Amish. The Amish 'court.' A young man 'courts' a young woman of equal or near equal age. The young woman has free will to accept the attentions of the young man or dissuade him (her family will if she not interested). The Amish also allow their young to go and 'live among the English' to decide if their (Amish) 'ways' are the right lifestyle for their young adult children.
Pedophilia, by definition, is 'an abnormal sexual desire, by an adult, for children. Puberty is notwithstanding by definition or by law.