Older brother steps in to help sister during father-daughter dance routine

The teenager filled in for his dad, dancing onstage with his sister.

An older brother warmed everyone's hearts when he stepped in to help his little sister for her father-daughter dance routine, after her dad couldn't make it to the event.

In June, Patrice Thompson shared an Instagram video featuring her 14-year-old son Micah sweetly dancing onstage with his 6-year-old sister Harper.

"Pov. your teenage son didn't want his sister to miss out on the father daughter dance so he did it with her," Thompson wrote in text overlaid in the video, which has amassed over 2.5 million likes and over 20 million views since it was posted on June 9.

"Core memory for the team today," she added in the caption. "I don't know if he knows what an impact he's making as her big brother but she'll never forget this."

Speaking to "Good Morning America," Thompson said Micah and Harper have always shared "a sweet bond … especially being so far apart in age."

She said her ex-husband was unable to attend the event because of a work-related travel commitment.

Micah told "GMA" he agreed to fill in for Harper's dad for the opportunity "to get closer" with his sister, noting that she is turning 7 years old soon.

"Especially considering the fact that this is something she is looking forward to, I just felt super proud being able to do this," he said.

Of the duo's sweet performance, Thompson added, "It was just so sweet to see them. I think by the end of it, when [he] lifted her up … it just totally wrecked my heart in the best way."