JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html>
<head>
  <style>

  body { font-size:16px; font-weight:bolder; }
  p { margin:5px 0; }
  </style>

</head>
<body>
  <table>
      <tbody>
          <tr>
              <td>
                  <input id="1" type="checkbox" value="1"/>
              </td>
              <td>
                  <div id="a4">
                      <button id="b">bb</button>
                  </div>
              </td>
          </tr>
      </tbody>
  </table>
</body>
</html>

JavaScript

$("#b").click(function(){
    alert($("#a4").parent().siblings().children("#1").val());
});