Last Flight. Last Healer Mysteries, #4

In book four of the Last Healer Mysteries series, Katie and Joe witness the deadly crash of a prototype aircraft and save the life of one of its occupants. After Joe discovers evidence of sabotage, Katie insists she is capable of investigating the crime despite being almost nine months pregnant. Someone planted an explosive device in the aircraft, killing the company's founder and jeopardizing the struggling startup's future.
Was the attack meant to destroy the company, or was it something more personal? As Katie and Joe hit one dead end after another, they learn the killer isn't finished. With time running out, they race to save the next victim, but with people dying, a murderer on the loose, and Katie in labor, what's a Healer to do?