The most formidable adversary in an argument may be a young teen. Between the ages of 10 and 13, conflicts with parents surge. Children this age become more independent and begin to forge their identities. At the same time, brain development makes them more impulsive, sensation-seeking and sensitive to peer pressure. The tumult can take parents by surprise, especially because the period right before adolescence is often relatively harmonious. For parents, learning how to effectively argue with tweens and young teens is crucial. Navigating disagreements over screen time and sleepovers sets the stage for conflicts over bigger issues—like sex and alcohol—that come up later. Therapists say argumentative young teens are healthy ones. They are learning how to handle disagreements and advocate for their own point of view, skills that are critical for successfully navigating adult relationships. Arguments also indicate that children are separating from their parents and asserting themselves. “It is worrying if [arguing] doesn’t happen,” says Brad Sachs, a family psychologist in Columbia, Md. More deferential children “may not be doing the hard work necessary to forge an independent identity.”