Hi, Ricco - welcome!
I was wondering what the solider said to the surviving member receiving the flag
Each of the military services has its own regulations for this, so it would depend on which one was conducting the ceremony. For example, the Army's FM 3-21.5 says
Upon presentation [of the folded flag], the CAO renders appropriate remarks such as, “As a representative of the United States Army, it is my high privilege to present to you this flag. Let it be a symbol of the grateful appreciation our nation feels for the distinguished service rendered to our country and our flag by your loved one.”
The origins of the flag-folding method are a bit of a mystery. My best guess is that the "tricorn" method was originally created as a practical way that a small number of soldiers could fold a large flag while keeping it clear of the ground.
Best,
Peter Ansoff