After 10 years, a mother can no longer deny that her child does not look like her or her husband. She decides to do a DNA test. She finds out that the kid is actually from completely different parents.
Wife: "Honey, I have something very serious to tell you."
Husband: "What’s up?"
Wife: "According to DNA test results, this is not our kid."
Husband: "Well you don’t remember, do you? When we were leaving the hospital, we noticed that our baby had soiled its diaper. Then you said, 'Please go change the baby, I’ll wait for you here.' So I went inside, got a clean one and left the dirty one there."