Twitter Rio Smith, center, with her grandparents Valerie and Wilson Ovenstone.

A couple’s heartwarming way of wishing their teenage granddaughter a good day at work is sending positive vibes around the world.

Valerie and Wilson Ovenstone take turns standing outside their home in Methil, Scotland, each morning to wave to 17-year-old Rio Smith as she travels past them on the bus.

Smith shared footage of her grandparents’ daily act of kindness to Twitter last week.

Every morning my Gran or Grandad stand outside and wave to me when am on the bus to work😭💔 pic.twitter.com/8zWEPH211X — Rio (@Riosmithh) October 19, 2017

The video lasts only four seconds, and it’s easy to miss Smith’s grandfather waving at her from behind a wall on his property.

The feel-good message that underlines the clip has sent it viral.

Smith said her grandparents began the morning ritual when she started work at her first “proper job.”

“They said they were so proud of me,” she told HuffPost. “They just started going out every morning and waving me on my way to work.”

“It makes me smiles every day seeing them do this for me,” she added.

The blink-and-you’ll-miss-it footage has so far garnered more than 45,000 retweets ― something Smith said she “just can’t believe.”

Her grandparents, meanwhile, said they were “overwhelmed” at the response and “everyone’s lovely comments” — a sampling of which are below:

Cherish them, Rio — Sam van Geffen (@GeffenSam) October 19, 2017

In love with this ....best tweet today 😍😍😍😍 — Donna (@DonnaDlm71) October 20, 2017

Oh my god this is too cute 😭 — rab (@robyntaylor_x) October 19, 2017

This is the cutest thing I’ve seen in my life 😭 grandparents are so so precious ❤️ — danielle♔ (@daniellereganxx) October 20, 2017

Each morning my mum waved when I was a bairn going to school. I walked. I stopped. I waved. I Walked. I Stopped. I Waved again. I miss that — gordon morris (@uniteddundee) October 19, 2017