A female friend of mine is trying to trick her husband into having a second child with her, would I be wrong if I told him?

Friend is trying to trick her husband into pregnancy - would I be wrong if I tell him? Or if I don’t?

Super shortened - if more details needed, please ask. I’m m late 30s and have known friend for 1.5 years.

They have one kid (2F) together and he has told her no more. But she says their daughter needs a sibling because she gets sad when leaving social situations to go home. I have met Husband and seen him in passing a few times, but other than a quick “hello” we continue on our separate ways. She has stopped taking pregnancy precautions without telling him because it’s ‘the right decision and he’ll come around eventually.”

But if my partner was trying to get pregnant without my knowledge and someone knew that, I’d want them to tell me regardless of who they are (as long as it’s true/not said with malicious intent). Help?
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I can't believe so many people support her deception.. Talk about a bunch of simps. Saying I shouldn't tell him is the same as saying you support paternity fraud, or rape by deception.. Shame..
A female friend of mine is trying to trick her husband into having a second child with her, would I be wrong if I told him?
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