Diapers
One day soon after the birth of their new baby the mother had to go out to do some errands. So the proud papa got to stay home and watch his wonderful new son. Soon after the mother left, the baby started to cry. The father did everything he thought he could do but the baby wouldn't stop crying.
Finally dad got worried and decided to take the infant to the doctor. They see the doc and he starts his exam after hearing that the father did all he could do. He looks in the baby's ears etc. and goes to the diaper area. The doc undoes the diaper and finds that the diaper is indeed full. "Here's the problem" doc says. "He needs a change." The father looks perplexed and states "but the package says it is good up to 8 to 10 lbs!"