I wish I could have said, "Mommy, I know you're trying to make me feel better, but my mind is telling me the opposite: 'It's NOT going to be OK.' And my body seems to be responding to my mind. My heart is racing, my palms are sweating, and my tummy feels funny. It's hard for your loving words to overpower what's happening inside of me."
Here's what we know: The stress response is hardwired into our nervous system as a protective mechanism devised to enact the fight-or-flight reaction to threats. Anxiety mimics this response. As such, when your child is knee-deep in anxiety, a rapid stream of chemicals is dumped into the body for survival. This makes it difficult to think clearly and, subsequently, for words of reassurance to sink in.
Try this: Respond to your child's nervous system first. Help them calm down with deep breathing. This can take the mind and body from fight-or-flight to rest-and-digest mode.