Bain Kern wanted to crew a starship and explore the galaxies. But as an orphan on a colony world in the path of an alien invasion he had no real hope of his dreams ever coming true.

Sunsinger Chronicles Book 6: University
It was the chance of a lifetime, to visit Centralis, home of the Commonwealth Council and the Commonwealth Upper University. While Lin testified about Sunsinger's visit to the Mashrami home planet, Bain explored the grounds of the university with his new friend, Gorgi Cole. Then a researcher was attacked, his laboratory ransacked and deadly cultures stolen. With the possibility of a plague being loosed under the domes of Centralis, Bain and Gorgi knew they had to help. But it could cost them their lives.

Sunsinger Chronicles Book 7: Leap Ships
Commonwealth history says part of the reason for the Downfall was because some people were classed as mutants and made into slaves, and the slaves eventually rebelled. Bain and Lin go on an exploring mission and meet Leapers descendants of people who escaped from the abuse and slavery of First Civ. Leap ships travel vast distances in a few heartbeats by slipping through the fabric of space and time. Journeys of years with Spacer pilots take days on Leap ships. Captain Lorian and the crew of the Estal'es'cai have come to see if anything remains of their galaxy and the civilization where their ancestors originated. What Lin and Bain do on meeting the Leapers could affect the future of the Commonwealth. Then, while exploring a desert world that could be the birthplace of the Leaper race, they run into an old friend. Or is he an old enemy?

The Sunsinger Chronicles Book 5: Fever
Sunsinger's crew joins the Rangers on a mission of mercy where time is the enemy along with a plague created by the alien Mashrami. Bain and Lin help to deliver medicine to hopefully prevent and cure the plague. When they come to a planet where the colonists are uncooperative, they start to unearth secrets better left buried.