Tom Cittadino was marching in the parade when the teen hande him the letter.
The letter, signed Carly, calls the veteran her hero. Cittadino and his family say they hope someone can help him connect with Carly to say thank you.
A family member said the teen was spotted handing out letters to several veterans at the parade.
Read the full text of the letter below:
I will never fully understand what you went through but I do recognize, appreciate, and honor each and every sacrifice you made for our country. You truly are so brave in all you do. Your hard work helps me and my family live a safe life. Find something beautiful in your life everyday. You can always find light through the darkness -- even on worst days. Never forget: you are my hero.
Love, Carly (age 15)
This story was originally published by Amy Abdelsayed on KTNV in Las Vegas.