A high school student asked his best friend's little sister, who has Down syndrome, to prom, and the heartwarming "promposal" was captured on video.

Shaedon Wedel, a senior at Newton High School in Newton, Kansas, had been planning to ask Carlie Wittman, 15, to be his prom date since the beginning of the school year, and he finally did so last Friday.

Wedel, 18, posted a video to Facebook that shows him walking up to Carlie's doorstep with flowers, a bag of Doritos and an amazing shirt that said: "I know I'm NACHO your typical Dorito but... I'm going to be CHEESY and ask: will you go to prom with me?"

He then officially asks her, "Will you go to prom with me?"

Carlie can barely contain her excitement and covers her face in disbelief before accepting and giving him a hug.

Shaedon posted photos and videos of the "promposal" online, and they've quickly gone viral.