Give each guest a piece of paper and have them write down a baby related question such as:
How you get your baby to burp?
What do you do for a diaper rash?
How do you prepare formula?
How do you get your baby to go to sleep at night?
Then have them fold the paper so that the question can't be seen and have them pass it down to another guest. Then have that guest write down an answer to a baby related problem. This can be but doesn't have to be the answer to the question they just wrote.
Keep in mind they have no idea what the question is! Then just read the questions and answers and have a good laugh!