My dad bought an eighth when he was like 25, and said he smoked one small joint before he went out one night, and got soo paranoid at the bar that he thought everyone there wanted to fight him. He went home, and left the rest of the eighth in a drawer, which he threw out like a month later. So my dad has blazed like maybe a eighth of a gram in his life. He can however outdrink me by a very large margin.
Both my parents know I smoke, but they're both chill about it.