Poison ivy

Poison Ivy is a plant that mentioned in Diary of a Wimpy Kid: Old School.

When Mr. Jefferson sets up a fire and told the rest of Greg's cabinnates to get some kindling to a fire but nobody knew what kindling was, so they brought everything back as they thought might burn. But his son Rowley came back with weeds and tossed onto fire, which was totally smothered over the fire. But the next morning, it turns out that the weeds was actually poison ivy which was placed onto fire, Rowley woke up covered with spots. His father Mr. Jefferson woke up too and he discovered that he has trouble breathing as he inhaled the fumes and gotten it in his lungs. The nurse called their wife Mrs. Jefferson to come pick them both up and left.