jQuery - conditional form validation

Question

Hello, I would like to us jquery validation. Forms are generated by cms, so names of form elements are unknown for jquery.

The case Each time, a user has choosen a radio-button with value 'maybe', the following textarea has to be required.

The form-code

<div class="rb">
  <input type="radio" name="fItem44" value="yes" /> yes
  <input type="radio" name="fItem44" value="no" /> no
  <input type="radio" name="fItem44" value="maybe" /> maybe
</div>

<div class="rm">
  <textarea name="fItem48"></textarea>
</div>

<div class="rb">
  <input type="radio" name="fItem51" value="yes" /> yes
  <input type="radio" name="fItem51" value="no" /> no
  <input type="radio" name="fItem51" value="maybe" /> maybe
</div>

<div class="rm ">
  <textarea name="fItem55" ></textarea>
</div>

...

Thanks in advance jk