This child,
is the one chosen by Jiang Chen.
Of course, with the child's strength, let alone executing evil ghosts and dispelling ghostly aura, he would probably be devoured with no bones left at the sight of an evil ghost.
For this reason, Jiang Chen specifically left him the Sixth-Class Divine Talisman.
With this talisman, he can enslave six ghosts.
The six ghosts are also known as the Six Divine Generals, all of whom possess the cultivation of Golden Immortals. The combined force of six Golden Immortals is more than enough to ensure local peace, regardless of dispelling the ghostly aura.
The Nanbuzhan Continent, as the main base of the Human Race, would not permit creatures like demons and ghosts of Taiyi Golden Immortal Level or above to emerge into the world.
After all, the human race is not without its own experts.