Even though the Empress didn't really like Nial's idea because it could be considered a reward rather than a punishment, she could tell that Nial thought a lot about what they should do with Celine and her family.
Celine's parents were commoners without great talent. They had barely reached the Mirae rank and couldn't be considered powerful in any way. Even their Familiars were extremely weak.
Meanwhile, Celine was currently only at the Origin rank. She was only six years old but she had great talent. Her future was bound to be filled with obstacles and opportunities, which would allow her to become strong enough to influence the Lacardian Empyrean Void.
Nial wanted to make use of that. Thus, he told his mother that Celine should become his servant and that her parents should be trained as servants of the royal palace.