The State of Missouri executed death row inmate Christopher Collings by lethal injection Tuesday evening for the 2007 abduction, rape and murder of a 9-year-old girl.

Collings, himself a father of two now-grown daughters, was convicted of killing Rowan on Nov. 3, 2007 in the tiny southwestern Missouri village of Stella.

Collings became the 23rd inmate executed in the U.S. this year and the fourth in Missouri, one of the most prolific death penalty states in the nation. Here's what you need to know about Collings' execution. In his last words, which he wrote out ahead ...