React memo creates rerender

The second argument of React.memo() must be a function that returns true if the component don't need to be rerendered and false otherwise - or in the original definition, if the old props and the new props are equal or not.

So, in your code, the solution should be just change the second argument to:

export const ChildComponent = React.memo(
  () => { ... },
  // this
  () => true
);

Which is gonna tell React that "the props didn't change and thus don't need to rerender this component".