Tools on the Calendar

The oldest is home sick from school today. He was fine yesterday. He was fine last night when I left for the Scrabble fundraiser. He looked fine when I peeked in on him when we got home late last night. But this morning, upon waking up, he informed me his throat was sore and he felt awful. His eyes are red. His glands are swollen.

We had plans for today. I had errands to run this morning, the oldest had a friend coming home with him after school, and the entire family had plans to go out this evening. But an unexpected virus has thwarted all that.

throw a monkey wrench into
idiom
Sabotage or frustrate a project or plans. This transfer of industrial sabotage—that is, throwing a tool inside machinery—to other subjects dates from the early 1900s.
"throw a monkey wrench into." The American Heritage® Dictionary of Idioms. Houghton Mifflin Company, 1992. Answers.com 19 May. 2006. http://www.answers.com/topic/throw-a-monkey-wrench-into