how to access a child of a react dom element?

Question

For example, I have a variable called show which stores a react dom element.

let show = (
<section id="moreInfo">
    <div id="title"> ... </div>
    <div id="list"> ... </div>
    <div id="other"> ... </div>
</section>
);

How do I access show's child element "list" or "title"?