Watch: The delightful reaction of an old man learning he's going to be a grandpa.

If you’re reading this at work, you’d better close the door — because this video is so emotional, it’s possible you’ll start sobbing into your keyboard. (Happy tears, we promise.)

At least, that’s how this adorable dad reacted when his daughter broke the news to him that she was pregnant and expecting his first grandchild. Get your ‘awww’ sound ready, folks.

Take a look:

The accompanying post on Reddit, apparently by US woman Jessica Vigansky, explained the grandpa-to-be was lonely prior to receiving this lovely surprise.

“I am his only child and my mother passed away 20 years ago. He has been asking us for grandchildren since our wedding night,” she wrote on Reddit.

“I think he is happy.”

We think she might be right…

What was your reaction to this video? And if you have kids, how did you first tell your family you were pregnant?