Those who have tried to help thank you, but it in't working. I have gone through the Drow city and all that and need to give Adalon her eggs. I went to speak to the svnerblin guys and they don't say anything about a demon. I already killed one demon in the beggining of this chapter. What am I doing wrong? Please help and thanks in advance.

That means you must have dropped or misplaced your light gems somewhere along the way. Maybe you can cheat (CreateItem) or use the Shadowkeeper to add it into your inventory and get the gem, but I do not know the item code for the light gem. You might be able to access the list of items in the game with Shadowkeeper or the item editor. Or you can just use the "MoveToArea" code (and warp to the Underdark exit map)to bypass the Underdark levels, but you will lose out on some experience.

Sounds like you dropped it. Apparently things disappear after 3 days but not critical items. Have you retraced your steps?...sold it? (Is it sellable?) Put it in a gem bag (not sure if you can) or bag of holding? It's not gonna be easy to see on the floor but that's not to say it's impossible.
One word of advice when you do eventually leave the Underdark. Be careful when your stuff (Drow) turns to dust. I'd stockpiled it and it overloaded my inventory dropping important stuff on the deck to make way for it. I lost the Wave Halberd Blade forever due to this. Hope you get sorted.

If you already have the real Dragon Eggs, get out of the Drow City and go back in the cave where you first met Adalon. If you can't get into the cave, it's because you don't have the light stone. If you don't have the lightstone, then I don't know what to tell you.