Sarah Bromby, a pregnant mother from Scunthorpe, filmed the moment she told her five-year-old son that he was going to be a big brother.
The video shows an elated five-year-old after realizing that his mother was serious and a baby was, indeed, on the way.
Looking at two pictures of an ultrasound scan, the boy screamed in delight: "Are you really having a baby? I’m going to be a big brother!"
Still overwhelmed by the news, the five-year-old shows an instinctive protection towards his new sibling and says: "He can sleep in my bed if he wants!"
The video was uploaded on Facebook and has been viewed more than 700,000 times.