If you are a new parent, and everyone always seems to be telling you how to raise your child, in particular your parent-in-laws, perhaps this lovely letter may be of assistance in getting them off your back:
Dear Mother & Father-in-Law,
Please do not try to tell me how to raise my kids.
I’m married to one of yours and believe me, there is definitely room for improvement!
Sincerely
Your Son-in-Law.
That should do the trick! ;)