HELP! iPhoto dissapeared....

Can´t open my iPhoto application in the dock, there´s a " ? ".....I can´t find it in applications anymore. The only way to see the pic´s is when I wan´t to open something with an application, then there appears that "media" part/whatever...there are the pic´s then. so they are still there. I didn´t delete anything or used iPhoto since a few days...Please help...all the pic´s of my son are on that and two of me I really like...

Download a program called Pacifist. Pop in your restore disc and reinstall iPhoto using Pacifist.

ok I´ll try. thanx a lot!