Fred came home from University in tears. “Mum, am I adopted?”
“No, of course not,” replied his mother. Why would you think such a thing?
Fred showed her his genealogy DNA test results. No match for any of his relatives, and strong matches for a family who lived the other side of the city.
Shocked, his mother called her husband. “Honey, Fred has done a DNA test, and… and… I don’t know how to say this… he may not be our son.”
“Well, obviously!” he replied.
“What do you mean?” She asked
“It was your idea in the first place,” her husband continued. “You remember that first night in the hospital when the baby did nothing but scream and cry and scream and cry. On and on. And you asked me to change him.”
“Well ….. I picked a good one I reckon. Ever so proud of Fred.”
Explanation: This joke plays on the double meaning of the word “change.” When Fred was a newborn and wouldn’t stop crying, his mother asked her husband to “change him,” meaning to change his diaper. But the dad misunderstood (or pretended to) and literally swapped the baby with another one. The humor lies in the absurdity of the situation and the dad’s nonchalant reaction to what should be a huge revelation.