Hi, your cousin is right it DOES have springs, what may have happened is the springs may have become 'misalligned' or have somehow worked themselves over the housing they sit in. To check you'll need a triwing screwdriver to remove the bottom cover(black usually unless your DS is pink in which case it could be white) there are 5 triwing screws you can see and also another 2 in the battery compartment. Once removed you should be able to remove the cover and in turn the shoulder buttons. remove the springs and place them on the little 'pegs' on the shoulder buttons (L&R) before replacing the buttons back in their correct positions. If any of the buttons or the springs are damaged you can easily buy a completely new shell off E-bay for around £7 which includes all the buttons etc required to give your DS a new lease of life. If you decide to replace the shell as well there's a very good guide here: http://site.powergamingparts.com/RepairNDS.html
you need any further advise please feel free to e-mail me jonashuk@aol.com
Good Luck
Jon
Jon Nash
March 2008