Why did my family get weird I asked them about the Kumbh Mela?

ABCD here. I was on the phone with my family and someone made a joke about the Kumbh mela. I then asked them what happens at the Kumbh mela and it got super awkward, and they all wanted to change the subject asap. Is there something wrong with the Kumbh mela or could there be a more personal reason for the reaction I got? My family is Hindu and Buddhist btw.