Sydney

 is a relic hunter (This is possibly a referance to the Character from the show Relic Hunter, who is also named sydney) the player will meet when hunting for the Declaration of Independence. If she survives the quest and gets to Rivet City, she will retire from relic hunting and become an ammunition vendor in Underworld. If you get into a fight in the Underworld, Sydney will fight alongside you.

Problems
Sydney will sometimes be found dead in Anacostia Metro Station during her post-quest journey from Rivet City to Underworld; apparently killed by a Raider. Though the task is painfully dull, it is advised that you escort her (if you find her alive in Anacostia Metro Station) if you want to have a sure opportunity to buy ammo from her later.

The alternative to holding her hand through the tunnels (she walks so slow) is to clear them in advance. Starting at Anacostia Metro Station make your way up the Red Line north to the Museum Station exit. Turn your light and your radio on to draw all the creeps out of the corners, bust heads all the way through and there will be nothing left for Sydney to encounter. I've done this and then walked her through and there aren't any trigger events, nothing new spawned to attack us (xbox360). If you haven't already, you can still clear the lines directly after handing in the quest, head to Anacostia Metro Station, she should already be there, rush in ahead of her, fight your way down the line, come out at the museum exit and then shoot-up any mutants that spawned in the mall bunker-zone and you're set.

Sydney's Father Quest
In the Statesman Hotel (Mid Level) (rescuing Reilly's Rangers) you'll find A Note from Little Moonbeam's Father, which is directed to Sydney from her father. Show the Holodisk to her and she will give you her Sydney's 10mm "Ultra" SMG and a supply of ammo.

(Note: There is an exploit where the player can repeatedly select the option to give her the holodisk, this is done by following the action above, then reinitiating conversation with her. The player then selects "Since we're done now, why don't you tell me about yourself?" >"Nice gun. I've never seen one like that." This makes the "So, whatever happened to your father?" option open up again, which once selected gives the option to give her the holodisk.

Equipments
Sydney's 10mm "Ultra" SMG (unique SMG, 59 DAM at 100% CND) There is also an ammo supply in the Ninth Circle, that belongs to Sydney. It requires her key.

Apperances
only appears in Fallout 3.

Behind the scenes
is based on character Sydney Fox from the TV show Relic hunter.

Glitch / Exploit

 * It is confirmed that If you do not talk to Sydney prior to finding the Declaration of Independence she will disappear from the hall at National Archives. You will still get the mission to fend off mutants if you approach her position (The Super Mutants will spawn.) She won't be at Rivet City / Underworld or somewhere else after that.

''-Note- On the PC version I did not talk to Sydney, but retrieved the Declaration of Independence alone. When I approached her, the Super Mutants spawned. When she joined me, the Declaration disappeared from my inventory and reappeared in the safe where I had to get it another time.''

On the PC version, you can use the console to reset Sydney so she appears in the rotunda after the fight in the rotunda. These commands were taken from the fix for the Bigtown robot quest bug (http://fallout.wikia.com/wiki/Big_Trouble_in_Big_Town#Robots) You can then talk to her and continue the quest. If you've already picked up the Declaration of Independence, you'll need to use more console commands to remove and then add the quest item to your inventory to trigger completion of the next step of the quest. After that, you should be able to complete the rest of the quest normally. she will leave the area and usually is nowhere to be found (not everytime). It is also possible by refusing her proposal to bug the Stealing Independence quest. -Note- Checked you can meet her in the wasteland, last time I saw her at the gates of Republic of Dave, but she will not copperate in natural way, to reset use the console.
 * PRID 3a77
 * kill
 * resurrect
 * disable
 * enable
 * player.removeitem 3a7f 1
 * player.additem 3a7f 1
 * When speaking to her in the Underworld to get the Sydney's 10mm "Ultra" SMG and ammo, you can ask about her father again, and get the conversation option to tell her about her father again, and get another SMG. This can be done repeatedly. Note that switching from one instance of Sydney's 10mm "Ultra" SMG to another in your inventory has been noted to cause the game to crash for some people on the Xbox 360 version.
 * After dealing with supermutants in National Archives and then refusing her proposal to cooperate

Exploit

 * If you wish to keep her as an extra NPC you can do so easily. She will stay with you as long as you do not complete the Stealing Independence Quest. So do not return to Abraham Washington. A few drawbacks with her as an NPC. She cannot be equipped with any new weapons or armor, she cannot be given any items to hold, she can die permanently, she cannot be told to change tactics or to wait (if you are holding the Declaration of Independence), she has to be manually healed via dialog and she has the health of an average human raider and can be downed quite easily. Overall a decent fighter but more trouble than she's worth.  However, she is handy in overcoming the 1-humanoid NPC companion limit - in one case, a 4-man team was made with the Vault 101 Dweller, Sydney, Dogmeat and Charon.


 * Unlike real companions, she does not heal to full at the end of a successful battle. You can still give her stimpaks by talking to her; which she will use immediately.