Six seconds could be tricky, but apparently it's important, because research shows that if we hold a hug for at least six seconds, we 'optimize the flow of mood-boosting chemicals'. If I tell Fred what's going to happen, he will refuse - that is what teenagers do. From my days in the Vietcong, I know that the only approach is the ambush. I'll wait around a corner this evening, keeping away from breakables, grab him and hold on for as long as possible before he shakes me off. I will then post the results of this six-second hug research, hopefully not from the fracture clinic.