Replied by Mama To Many (Tennessee) on 05/01/2014
Dear Gizmo's Mom, I do not know if the silk thread thing would work. The thought of it makes me feel a bit squeamish. :)
Another option would be to put an activated charcoal tablet onto the spot nightly and let it slowly dissolve there. If you try the thread thing, I would do this afterwards to help it heal.
Comfrey helps old scars and helps things to heal. She could try putting a little comfrey poultice against the spot a few times a day, 20 minutes at a time. A little of the dry herb or powder wrapped up in a little piece of paper towel or coffee filter. You can use the herb, straight, too. Again, this could be used to help heal if you do the thread thing.
Do let us know what you try and how it goes!
~Mama to Many~