How can I sort this array in PHP? I want to have the most recent dates first. I can't do the sort in MySQL as the date field is coming from several different tables. Three rows shown here - there are more than 600 in total.

```
Array
(
    [0] => Array
        (
        Translator => Array
            (
                [id] => 1482
                [name] => Jane Doe
                [last_project] => (null)
            )
        )

    [1] => Array
        (
        Translator => Array
            (
                [id] => 1024
                [name] => John Doe
                [last_project] => 2013-06-25
            )
        )

    [2] => Array
        (           
        Translator => Array
            (
                [id] => 32
                [name] => Tom Doe
                [last_project] => 2009-07-10
             )
        )
)

```