While I find it an interesting article and wish the young fellow all the best, hopefully he will soon move on or this really isn't his main purpose and only an angle for a story to help make Mathematics and Science more palatable and interesting to a wider set of readers.
It is incredibly unlikely that anyone will ever make much headway with anything remotely like a direct attack on Relativity. It has already survived and increased rather than becoming depleted within the macrocosm. It is worthy of note that Einstein did not set out to disprove Newton, nor did he. He just helped define the limits at which Newton begins to breakdown. Newton still works up to a point just as Einstein still works after nearly 100 years of massive advancement. Einstein’s theories limitations were already well underway while he was alive in the form of Quantum Mechanics.
Presently the area of best odds for fine tuning the definition of those limitations is in the areas of particle physics and the nature of gravity, especially discovering if it is discrete at the Planck level, Lee Smolin’s Three Roads to Quantum Gravity
is still enlightening on this subject as are the somewhat famous debates between Smolin and Susskind
. If this 12 year old is to really discover something of such extreme value it is likely in these arenas.
None of that diminishes the importance of such articles or such people. It still amazes me how much superstition permeates human society.