Do `aria-` tags include children elements?

I show and hide some inputs in the same form depending on the status of a radio group. For accessibility, I add and remove aria-hidden=true to the parents of these inputs by writing a JavaScript code.

In short my code is like this

<fieldset>
  <input type="radio" name="hello" value="1" />
  <input type="radio" name="hello" value="2" checked />
  <input type="radio" name="hello" value="3" />
</fieldset>

<div class="hidden" aria-hidden="true" data-radio-hello="1">
  <textarea></textarea>
</div>

<div class="active" data-radio-hello="2">
  <input type="text" />
</div>

<div class="hidden" aria-hidden="true" data-radio-hello="3">
  <input type="checkbox" />
</div>

In the example above, the JavaScript code adds a class to the matching parents, adding aria-hidden=true to hide them as the states of the parent radio inputs change.

In this case, according to the example above,

<textarea></textarea>
<input type="checkbox" />

Would I be able to correctly mark these elements with aria- and hide those two elements from screen readers?