Multiple 'child of' constraints problem

I am having trouble using child of constraints.

What I want :
What i’ve got :

The green bone at the center receives ¼ of the influence of each of the 4 surrounding bones through the child of constraints.
2 1 1 2

And I wanted the root bone at the left to be the parent of the 4 constraint bones and control them.
But I failed.
When the rotation value of the root bone is 0, the green bone is well fixed between the constraint bones, but when the root bone rotates, the green bone leaves its place.
Also, changing the scale value of the root bone causes the same problem.
4 3

Attached the blend file used to shoot GIF.
I hope this helps you write an answer for me.
multiple child of problem with rotation of parent.blend (97.3 KB)

Might help to tell us what you are after on your animation because you want the green bone to follow root, but you told it to rotate as the corner bones rotate not root.
What else are you going to do that requires you to stay in the center of the square? I’d be guessing but I think you need another bone and rig is this way. Now you control the square with one child of that is parented to root.

revisedsquare.blend (94.1 KB)

Thank you for writing the example file.

But this didn’t help me.
Because four child of constraints are missing.
The example I used for the question was actually a simplified version of the character rig
Here’s a GIF of the issue I had in the character rig.
To preserve the volume of the pelvis and hips and keep the silhouette soft as the character’s joints move, the bendy bones are installed on the sides and hips, and they have child of constraints targeting the surrounding control joints such as spine and arm.
They preserve the volume of the pelvis and hips and keep the silhouette soft.
So they move smoothly at the average position of the main control joints.
However, when the character’s root bone rotate, they leave their place and cause an ugly transformation.
This is the same problem that the green bone I first asked deviates from the center of the square frame.

In other words, I want the green bone to keep its place as the root bone rotates while maintaining the child of constraint for the four surrounding bones.

Try the exact same thing, but instead of “Child Of” constraints, use “Copy Transform” constraints.

EDIT: You probably don’t need it, but here’s a .blend file example:

Oh, I never thought of Copy Transform at all.
The two are almost similar, but seem to behave a little differently.
After testing for a while, the disadvantage of Copy Transform is that the position of the green bone is forced in the center of the target bones.
(The position in edit mode and pose mode is different.)
However, I have an idea to use Copy Transform and Child of together to solve this problem.
I got a hint thanks to you.
I will apply this technique to my rig and report results if it improves.
Thanks for the example.

OK but why doesn’t parenting work? Hope you find a solution anyway.