[jQuery] text of first sibling of a parent...How do I get it

[jQuery] text of first sibling of a parent...How do I get it


Still a newbie.
I have this:
<table>
<tr>
<td>
text I want to get
</td>
<td>
</td>
<td>
<div id="knowndiv"></div>
</td>
<tr>
</table>
If I have the div with id of "knowndiv" as an object (call it "obj"),
How do I get the text inside the first <td>?