Wasted efforts

I have a friend at age 18 still need people to worry , whenever i go out with him he always does stupid that will result in getting scolded. A lot of time i got scolded because of him , his family seems to protect him in any way , making him very childish . i tried explaining to him yet it failed, i try try telling his family but they think i'm trying to sabotage their relationship. i not your family so it not within my duties to help you. Grow up , don make a fool of yourself, nobody like it . life is stressful even without you interfering .