Hi Mayuri!
You can definitely do these meditations on behalf of loved ones. I generally stipulate their name and ask that any energetic shifts be for the "highest good of all." As I don't know what their journey is and what they're here to learn, I don't want to interfere with their unique path and any growth they are here to experience.
The more you use any energetic influence, the more engrained it becomes in your very being. So the more you invoke the blue light of protection, the stronger and steadier it will become (until it's just there, whether you're purposely invoking it or not).
With regard to the actors who are using these meditations, I know there are several, but as we don't have permission to use their names, we can't compromise their anonymity. Pete says Donna Karan uses them and has given us permission to let that be known.
All the best to you!
Wendy Greer
Learning Strategies
