Free from the author via KDP Select @
Amazon:
Panic at Emu Flat by Robert Elmer, 8th and last in his Adventures Down Under series of Australia-set tween/YA mystery/adventure thrillers, originally out from Bethany House in 1999.
What secrets do the growing shadows hide?
Patrick McWaid can’t understand why his friend Jefferson would leave the Lady Elisabeth to work on another ship. Sure, the Victoria is a much fancier paddle steamer, but Jeff’s new boss, First Officer York, is a tyrant and a bully. And when Jeff and the Victoria steam away from Goolwa, they leave a strange but valuable cargo behind—two crates full of ostriches!
The McWaids have no choice but to take on the extra load, and when they catch up to the Victoria at Emu Flat, Patrick has a run-in with the disagreeable Officer York. Once the Lady E arrives in Echuca, though, Patrick hears rumors that an officer from the Victoria has died. It could be York, but is Patrick somehow to blame? And now Jefferson has disappeared! Where could he be? No one on the Victoria is talking. What’s the big secret?
ETA: X-link from the Mystery megathread since the Publisher's Weekly review says that some of the stories are more faith-exploring parables than mysteries (YMMV as to "clean"-liness of content, though):
Free from the author via KDP Select @
Amazon:
Flesh and Blood, a short story collection by Michael Lister, in his John Jordan Mystery series starring a Florida prison chaplain