bubble Effect on the player

hi , I have a question.I want to use bubble effect on my player.
And follow my player.like this

I use this script[Instantiate(prefab, transform.position, transform.rotation);] on my player And my prefab use smoothfollw sript follow my player,but I want the prefab’s position is same way with my player running.what can I do.

bubble.transform.parent = player.transform;