This is a rant.!

So last week I announced to my husbands side of the family that were expecting our second baby. All happy congrats! But then I get a call from my sil today. Apparently my hubby's cousin is spreading rumors that I cheated on my husband. She's pregnant also. She's around 20 weeks, she's knocked up by some guy she cheated on her ex with. And now she's single and her family are soo unsupportive about it. Especially her dad (hubby's uncle) , he told her to abort it. I'm assuming she's spreading these rumors cause she may be a tad jealous becuz everyone's excited about my pregnancy and not so much hers. I feel bad for her but pissed for what she's saying. Now I don't know what to do. Should I brush it off and ignore this or should I talk to her or the family who's hearing this rumors.? Just really pathetic and annoying to have to be dealing something so high school.