decal moving with object

Hi everyone,

I got a magic effect that hits a box for example. On that position I instantiate something like a "hit" effect, its a particle effect thats explodes a lil. But if the hitten objects moves (the box is a rigidbody), the particle effect stays on the same position.

I thought I can solve the problem if I make the particle effect a child of the box, so it is following the movement. But it doesnt work. So how can I let my particles be connected to the box, and follow the exact movements?