Lillie made her friend Trevor's day when she walked into his workplace on April 25 and asked him out to prom.
Trevor works at Beau's Coffee in Wilmington, N.C., which owner Amy Wright describes as "a coffee shop that is run by people with intellectual and developmental disabilities."
Wright's daughter, Lillie, has been friends with Trevor for years.
"Lillie has always seen the value in every person - especially Trevor," wrote Wright on YouTube. "She couldn't wait to ask him to prom and he enthusiastically said 'YES!'"
The video went viral on Facebook, amassing over 350,000 views since being posted on April 25.
Adorable prom proposal goes viral
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