Why Did n't I Think of That is a song written by Bob McDill and Paul Harrison, and recorded by American country music singer Doug Stone. The song reached the top of the Billboard Hot Country Singles & Tracks chart. It was released in June 1993 as the fourth and final single from his CD From the Heart.\n\nWho sings why didn't i think of that
Let's think step by step below.
American country music singer Doug Stone
The relevant sentence in the passage is: "Why Did n't I Think of That" is a song written by Bob McDill and Paul Harrison, and recorded by American country music singer Doug Stone.

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Final answer: American country music singer Doug Stone