Pokémon Swap: The 6 Dolls

Join siblings Larry, Hank, Arthur, Thomas, Cody and Gary as they attempt to rescue the legendary Dream Egg from the evil hacker Chi and his two advisors.
To do so, they have to collect 6 dolls. Dolls that look suspiciously like their fathers who disappeared many years ago.
If they don't, Chi will destroy the egg and horrible bad dreams will plague the world.
What are the dolls' secret?
The final book in the trilogy.