Looking for advice on a bit of Easter bunny family drama...

We celebrate Easter with the Easter bunny. As in the Easter bunny hides eggs and brings the kids Easter baskets

MIL didn't raise DH with the Easter bunny being "real." There was talk of the Easter bunny but she always just gave DH a basket and took credit for the holiday.

Yesterday we were doing Facetime with MIL and she seemed to have "forgotten" that we do the Easter bunny. So she made a side comment to DS, who's 3, "oh so if the Easter bunny came to your house did he poop? Bunnies poop a lot." She continued on in front of the kids asking "well what candy did you buy for them? I only ever bought you the good stuff." DH keep redirecting her but it didn't really work out as we had hoped.

This all sounds so silly to type it out, but I guess DH and I are a bit stumped at how to set a boundary with MIL to get to respect about the way we are celebrating the holiday with our family.