Seals of Eternity. Book 6 of the Peacetaker Series, #6

A cruel and mercurial ancient deity, stranded on Earth for thousands of years, has been searching for his means to escape from his earthly confinement. The only two artifacts that will do the job, the Seals of Eternity, have been lost in the sands of time. Sed, the mysterious and shadowy figure of jackal, has killed thousands in his relentless search for the Seals. The 21st century sees him taking over bodies of delegates attending an archeological convention in Miami, in pursuit of the knowledge about the two Seals.
  When Stella's husband, Carter, takes their adoptive son, Gabriel, to see the newly opened exhibit of recently discovered ancient treasures in a museum in Coral Gables, he has no idea that once again the doomsday clock started ticking.