I'll add a little explanation about my initial advice. Here is where I am coming from: at the age of 2, your child is not yet able to verbalize his observations about what the environment is like when you are not present. I've worked in both a daycare and a preschool, and I've seen professional caregivers lose it and yell and scream. Whether this is a community center, a private preschool or an in-home babysitter, I would not leave my young child unattended in a setting where it was not required by law with someone who concerned me enough to be weighing the options. It isn't worth it.
There will always be people who don't get your kid, who are intimidated or jealous by the apparent intelligence, but whether they are wildly enthusiastic about embracing your child's unique gifts isn't the concern here, it is that a woman in subtly and not so subtly undermining a child's value with her comments. That isn't acceptable in any setting, much less one that is established for an enriching experience for children.
I've worked with my kids to learn to cope with rude teachers who were unfair. But when they crossed the line to diminishing our child, we got involved - whether our child was 7 or 17.
