wp_list_pages: how to show same level pages and child of current

Hi,

in WP 3.0.1 i’m trying to handle with wp_list_pages: i would like to make a menu where all the page of the current level are shown (let’s say brothers) and also the child of the current page.
Can somebody help me?

Example:
1. page 1
2. page 2
2.1 child 1 of page 2
2.2 child 1 of page 2
2.3 child 1 of page 2
3. page 3

Thanks!
Paolo