WATCH: Irish dad shocked as disguised son travels 6,000 miles for 80th birthday surprise

A wholesome clip of a disguised son's last-minute 6,000-mile trip to Ireland to celebrate his dad's 80th birthday has taken off online.

Cormac O'Brien travelled from California to Ireland to join his family's trip to mark his dad Tim's 80th birthday. 

A proud Corkman living in America for over 60 years, Tim O'Brien and his family planned a trip home to the West Cork town to mark his milestone birthday. 

Cormac, however, originally wasn't able to make the trip before deciding to "come at all costs" with his young daughter and surprise his father.

"My dad moved from Bantry in 1963 to join the US Navy. Then New York, Arizona and now he lives in California - where I live," Cormac told Iconic Media. "He is the oldest of seven O’Briens that are all still in Ireland.

"We always come back to Bantry for a visit. He chose to come here to spend his 80th and I couldn’t make it until last minute.

"I decided to come at all costs with my three-year-old to surprise him," Cormac explained before saying it "feels great to be back".

Disguised with a fake moustache, a wig, sunglasses and a cap in the viral clip, Cormac hides in plain sight before delivering a pint of Guinness and whiskey chaser to the table and whipping off his disguise to surprise his dad. 

Jimmy Crowley's pub erupts in laughter as the camera pans to a delighted Tim and the pair hug in a touching moment that has received over 23,000 upvotes on the popular Ireland thread on Reddit.