Study says you will be influenced more by new teen 's friends ' behavior . Family and friends will ` ` spread '' obesity , drinking , smoking , and even happiness . In a follow-up interview two years later , the same students answered similar questions and were also asked to name special romantic partners from the past 18 months . Results emphasize how to learn more about who your child hangs out with .
Study says you will be influenced more by new teen 's friends ' behavior . Family and friends will ` ` spread '' obesity , drinking , smoking , and even happiness . Results emphasize how to learn more about who your child hangs out with .