Weird Child-Parent behavior

Hi,

I have a GameObject of a gun.

The hierarchy is this:

1. Parent (Pivot for rotation)

2. Child - Mesh of object

3. Child - Location of barrel (to fire a bullet)

Whenever I change the location of the barrel, the parent transform changes as well.
I've linked a small video.

Why did the parent move as well? I want it to remain in the same spot.