Probably 4 or 5 years old at the neighborhood barbeques. There were always grownups willing to share their PBR, so I would go around bumming from my father and uncles. It was cold and tasted good. After I got grown one of the relatives reminisced about the time I picked up someone's full can and drank it and had to be taken home because I was staggering around. We were Methodists and some of the neighbors were Catholic so drinking was tolerated.
