grab the second child:

$(t).children().eq(1);

or, grab the second child <td>:

$(t).children('td').eq(1);

See documentation for children and eq.

I didn't see it mentioned here, but you can also use CSS spec selectors. See the docs

$('#parentContainer td:nth-child(2)')

Here's a solution that maybe is clearer to read in code:

To get the 2nd child of an unordered list:

   $('ul:first-child').next()

And a more elaborated example: This code gets the text of the 'title' attribute of the 2nd child element of the UL identified as 'my_list':

   $('ul#my_list:first-child').next().attr("title")

In this second example, you can get rid of the 'ul' at the start of the selector, as it's redundant, because an ID should be unique to a single page. It's there just to add clarity to the example.

Note on Performance and Memory, these two examples are good performants, because they don't make jquery save a list of ul elements that had to be filtered afterwards.