DS (14 nearly 15) is friends with my friend's son who is just over 3 years older. They've grown up close since my DS was born and the age gap never seemed that big. A few years ago they moved away but stayed in touch. Recently they've moved back and DS and his friend (now 18) have started hanging out again. Today DS went out with this friend and came back and said that they had been with friend to the house of his friend's friend (age 19). They just had snacks and played Xbox. DS came home on time and told me all about it. I mentioned it to DH and he's gone mad saying what am I thinking and that DS will end up drinking and smoking weed and wants to ban them hanging out (friend is good and doesn't smoke weed to my knowledge). AIBU to let them see each other as long as DS behavior stays good?