It seems like everyone in the 60s and early 70s was getting high - whether they intended to or not. John Kerry's mom once found herself in the latter group in 1972 during a protest against the Vietnam War. And she didn't even realize she was high until she showed up later on that night for dinner with John, who was making his first run for Congress at the time.

"My mother was supposed to meet us," Kerry recalled in his new memoir 'Every Day Is Extra.' "She was late. Finally, we saw her car pull up. She parked it in the middle of the street with the lights on and the engine running, hopped out and came into the restaurant."

And it only took one glance for Kerry to know that something was wrong with his mom. "Her pupils were enormous," he recalled.

So how did a straight-laced 60-year-old turn into a diehard hippie in one afternoon? Turns out, it wasn't from rubbing shoulders with long-haired protestors at the rally so much as watching the event within the vicinity of their pot smoke.

"She drove down from Massachusetts and found herself a place on the [National] Mall to watch the speeches," Kerry explained. "As the crowd filled in, her view of the far-off podium became obstructed by the sea of onlookers."

So to get a better vantage point, she did what Tarzan would do.

"Near some picnicking hippies, Mom climbed a tree and watched the rally from her own personal balcony....It turned out that for hours as Mom sat in the tree watching speeches, the hippies sitting below her were smoking joint after joint. To our amazement and eternal amusement, Rosemary Forbes Kerry had showed up to dinner secondhand stoned."