JSFiddle - React, Tailwind, and code Playground

HTML

<div class="section-content-parent">
   <span class="section-content-header">SPAN CONTENT</span>
    <div><p>Some more content.</p></div>
   <span class="section-content-subheader">SUBHEADER CONTENT</span>
</div>

CSS

.section-content-parent > * {
    display: none;
}

JavaScript

// store children in an array
var elems = $('.section-content-parent').children();

$(elems).each(function(index) {
    $(this).delay(1200*index).fadeIn(1000);
});