A video of a gay couple being told they are going to become grandparents has become a viral hit on Youtube a year after being uploaded to the site.

In the video, a young couple surprises the two men by asking what they think it will be like being grandparents, and the parents react with disbelief.

It is unclear what caused the recent surge in popularity for the video, which was recorded just before Christmas 2010, but one father’s particularly excited reaction to the news has proved popular.

One Youtube user said: “Every child should´╗┐ be born into a house with this much love and joy, the world would be a much better place.”

Another added: “I challenge anyone (with a brain, heart´╗┐ or soul) to see such genuine love and tell them it’s wrong.”