How should I make a empty GameObject, whose position is where the hand in animation is?

Hey,
I have a problem that I would love you to help me with it. So, I have an animation of a character walking, jumping and idle. I need to have an empty GameObject in the scene, so I can do somehow, that the empty is always, where the hand is. I am willing even to animate the GameObject frame by frame in Unity, but I need to solve this.

I have already tried creating the animation of the empty, to be exactly where the hand is, but there are 2 problems.

1. It is hard (almost impossible) to animate the GameObject because I do not know how to make Unity play the character's animation while animating the GameObject.
2. When I did it and animated the GameObject (the animation was not good due to not having any reference), sometimes it ran almost synchronized, and sometimes it was completely asynchronous. The animation had the same amount of frames, and the same speed set in the Animator, and both were set to Layer Default State.

Thank you very much.
Viktor Stopka