Thomas Rhett and his wife Lauren gave their daughter a very important lesson in respecting our nation's heroes on the 16th anniversary of 9/11.

Rhett and Lauren were in New York City on Monday (Sept. 11), and they took their adopted daughter down to meet some of the members of the fire department, where she posed for an adorably serious-looking photo in front of one of the enormous fire trucks with a fireman's helmet perched askew on her head.

"So grateful & honored to get to know some of the FDNY today," Lauren writes to accompany the picture on Instagram, adding,  "And on September 11th of all days. Remembering all of those who lost their lives 16 years ago today."

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She recalls sitting in her middle school classroom and watching the Twin Towers fall on live television.

"Meeting some of the men and women who serve our country, some of them who even served our country on that day 16 years ago, and seeing the photos of those who lost their lives from Ladder 25 on 9/11, was so surreal," she adds. "God bless the first responders of New York City & our country. Thank you Ladder 25 for having us & showing our girl around. She loved it :) #NeverForget."

The couple adopted Willa Gray in May after a grueling year-long process. They also welcomed a biological daughter, Ada James, in August.

Rhett and his family were in NYC in advance of his appearance on the Today Show on Tuesday (Sept. 12.) The singer released his third studio album, Life Changes, on Friday (Sept. 8). The first single from the project,"“Craving You," is a duet with Maren Morris that reached hit No. 1, and Rhett has released the second single from the album, “Unforgettable.” He’s been on the road on his headlining Home Team Tour for a large part of the summer.

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