Unfortunately i've been on the receiving of that exact same scenario. For 20 years I wondered why I was often being excluded from family gatherings and often sniped at when I was there. That turned out to be the work of a niece and her husband behind my back. Nobody thought to mention it to me, they accepted what they were told without knowing the facts. Now the facts don't matter because it's become their reality and the family is deeply divided as a result.
The lesson there is that if you sense something is wrong get to the bottom of it as soon as you can because unchallenged lies become facts in time.
