I would say something like "thanks for your opinion. I've researched this subject well and am comfortable with my decision." I may add "would you like to know why?" (they probably won't) or if I'm feeling spunky, I'll say "thanks, I'll give that suggestion the attention that it deserves." and leave it at that. Then I would change the subject.
I read a great article called "Pass the Bean Dip" (below) The principle is that you don't need to convince the other person that you're right, just confidently state that you have decided to parent this particular way.
L.
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This is from Joanne Ketch (http://goybparenting.com/)
I've found new moms often confuse boundaries and trying to convince someone of the *rightness* of their choices.
The best thing is to assert your boundary and *not* try to defend your choice.
Some family and close friend help.....
First, I learned early on that most of my choices were on a "need to know" basis. Most people don't "need to know". If asked "how is the baby sleeping?" Answer: Great! Thanks for asking! Want some bean dip?
"Are you sure you should be picking her up every time she cries?" Answer:"Yes! Thank you! Want some bean dip?"
"When do you plan to wean" Answer: "When she's ready. Thanks! Want some bean dip?"
Now, with some people you will need to set *firm* boundaries. They will need to be backed up with action (like hanging up, leaving the room or even the event). If it's a pattern of intrusion, for example. Practice kind but firm responses:
"I know you love us and the baby. We are so glad. Our sleeping choices have been researched and made. I will not discuss it again"
Also, don't confuse setting boundaries with trying to convince someone of the rightness of your choices. New AP moms often struggle with this. The boundary is that no one else has a right to tell you how to parent and create a hostile environment. You set boundaries by doing the above. Where new moms often invite problems is by citing authors, studies and sites to "defend" themselves. Each time you do so, you create more time for discussion and rebuttal and send the message that your decisions are up for debate. Don't defend your choices beyond generalities, and then only once or twice. "The doctor is in support of our choices. Want some bean dip?"
Finally, look them in the eye and say simply "I want us to have a good relationship. I want you to *enjoy* the baby. I'll parent the baby - you enjoy them. Let's not discuss this anymore. If you bring it up, I will leave the room."
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