Large number of a parent/childs fadein effect

I have an empty parent object that has eight children.

I would like to dispose this hierarchy multiple time in an matrix (48 x 48), similar to an array transformation.
Also I would like to fade those in while my camera pans out.

Would this required some Python scripting or should I be ok without.

How do I go from a parent/children group to 4 and then 9,16, 25…

Any of you done a similar project, if so I’m willing to contract some training to learn how to.

Thank you


Quick example