S.M.
I wouldn't be concerned about magnets on the head, but more if she eats it. When magnets get eaten, more than one, they can get stuck in the intestine and clamp two parts of the intestine together.
It was on the news last year, a little girl had to have surgery because the magnets were obstructing her bowls by clamping her intestines!
So watch out for all toys with magnets too.
Try Giovanni Organic hair gel (walgreens) for her whacky hair. Also Target sells clips for kids.
have fun.