Sorry to tell you, but Brady Mahgran is the youngest to thru hike the trail. High school senior who completed it solo to raise money for cystic fibrosis in 2017.
And I say, "Oh, that I had wings like a dove! I would fly away and be at rest; yes, I would wander far away; I would lodge in the wilderness; I would hurry to find shelter from the raging wind and tempest." Psalm 55:6-8