Teens and other adult influences
Parents often forget that they are not the only adults in their teenagers' lives, until this becomes either a problem, or a support, in the ongoing drama that is the teenage versus parent conflict. Single parents are more likely to be aware of, and utilize the other adults in their teenagers environment, actively seeking positive role models, of the absent parents gender. Thus a teenage boy's football coach can be an ally for the single mother who needs a male role model for her son.
A teenager's teachers probably see the teenager as much, if not more, than many parents. It may be a teacher who identifies that there is a problem, and calls the parents in to discuss their concerns. Some parents take this very badly, which is short-sighted of them; when raising teenagers, parents should be grateful for all the help they can get! It is not a criticism of the parent; teenagers are not always able to hide their problems from an observant teacher who has years of experience with a variety of troubled teens. Sports coaches can have a strong influence on teenagers, they may be the one person who is able to discipline a defiant teen, by virtue of the teens desire to be accepted into the team and praised for their achievements on the sports field.
Other adults that can influence teens may be relatives, such as aunts and uncles and often the grandparents who are less directly subject to the teenager's tantrums and bad behavior. Parents' anxiety about other adults being involved in their teen's upbringing may stem from a fear of criticism, of their authority being undermined and of the teenager preferring to spend time with the other adult, rejecting their parents.
In some cases this may be justified; some adults do not understand the delicate balance between support and discipline, they may allow the teenager free reign and naturally become far more attractive a proposition than the parents. In this case, the parents have no alternative but to speak with the adult and explain the situation; without dismissing the positive influence that the adult may have and not creating a situation where the teen believes their parents have deliberately destroyed the friendship. Parenting teenagers is a tough job, and other adults can provide much needed support.
Defiant teens will do everything in their power to find alternatives to their parents' discipline. In this situation, parents need to enlist the support of the teachers at school, relatives and sports coaches and any adult that may have some sway over the teenager. All these adult influences need to take a consistent approach to the troubled teen and the combined support may be all the teenager needs to find their way back to a more balanced and calm way of life. If this combined effort does not work, then there are professional adults the parents can turn to.