Finding the Little Lamplight Quest in FO3 GOTY

Good Morning all wastelanders! I am starting a new playthrough and haven't touched the game for about 7 years. I cannot remember how you start the quest for the Little Lamplight. IIRC, that quest will lead you to the slavers camp as well, so I can take them out too. Is this quest found as you progress the main story, or do I have to go looking for the quest? I remember that it was one of my favorite quest, and want to make sure I get that one done.

Thank you for the assistance with this!