One for My Baby

 is a quest in Fallout: New Vegas.

Quick walkthrough
Talk to Boone, who is located at the top of the Dino-Bite Gift Shop at night. He will mention his wife during conversation. Offer to help. Ask No-Bark Noonan about Boone's wife. He will mention the Dino Dee-lite Front Desk. Sneak in at night and obtain the Bill of Sale from the safe behind the desk. (go check bugs if you are having trouble asking her to take a walk) Ask Jeannie May Crawford to see what is in front of the Dinosaur. Put on your beret and lead her there (or put it on when in front of Dinosaur, it does not matter). Go back to Boone. Then assuming you followed the correct steps listed above, show Boone the Bill of Sale when he asks you for evidence of Jeannie May Crawford being the correct target. If you did not perform this however, have a high enough speech level and tell him "Their story didn't match up." After you complete the quest you can ask Boone to join you and he becomes your companion. Also you cannot recruit Boone to be a companion if you have a bad reputation with the NCR.

Detailed walkthrough
1. Go to Novac between 10 PM and 9 AM. Find the giant dinosaur and enter it. Once inside, head up the stairs and go through the door at the top. You should meet a man named Boone. Talk to him about his wife and you will receive the quest to find out who sold his wife off to slavers so he may kill them. He also gives you his beret to wear as a signal to fire on the person you bring in front of the Dino.

2. You are then given the task to talk to select inhabitants of Novac. Luckily, you only need to talk to one of them in order to progress in the quest. This person is No-Bark Noonan, an older man that seems a little out of his mind. You can find his shack behind the motel. Talk to No-bark about Boone's wife and he will tell you about strange business in the motel lobby. (If you have a high enough speech level you can finish the quest without evidence. Just talk to Boone after talking to No-Bark Noonan)

3. Head to the front desk of the motel and once inside check behind the counter to find a safe in the floor. This safe is locked and will require you to either lock pick it (easy skill) or pickpocket the key from Jeannie (there is no loss of karma). Inside the safe you will find a note titled Bill of Sale. This document tells of how Jeannie May Crawford sold Boone's wife off to slavers. Alternatively, you can have Boone kill her first, then take the key and go back for the evidence.

4. Now you have the evidence so confront Jeannie at night and ask her to take a stroll with you in front of the dinosaur. Once in front of the dinosaur put on the beret and Boone will kill Jeannie and your job is done.

5. Head up to Boone. He will ask you how you knew it was her (this is where getting the evidence comes into play) and you tell him about the bill of sale you found. If you did not get the evidence you can use speech on him but if that fails he may try to kill you or he may get angry, snatch his beret back, and say that he doesn't ever want to see you again (thus no option of him being a companion, obviously). If you told him about the evidence you can keep talking to him and make him become your companion. Upon joining you, you will gain the Spotter perk.

After accepting the mission, you can go talk to Manny and get him to walk in front of the dinosaur where Boone will kill him, whereupon you can get some good loot from Manny's corpse (including his beret which carries a +5 crit.hit) without getting any negative karma, though Boone will be angry at the lack of evidence as mentioned above and not be your companion unlss a speech check is passed (55). However the same +crit beret is given as a reward for completing the quest correctly (sending Jeannie May). If this alternative is chosen, the side mission of clearing out the building to the west should be completed and turned in first.

Bugs

 * If you cannot get Jeannie to follow you, try the following solutions:
 * Use the Wait function to move the in-game time between 9PM and 9AM. Suggest moving it to a comfortable time between then. Midnight seems to work well. (Confirmed. You may not actually be able to confront Jeannie, but if you talk to her during this time duration an option will appear in the dialog asking her to follow you to the front of Dinky the Dinosaur.)
 * Change your tracked quest and fast-travel out of the town. Return, retrack the quest, and attempt to confront Jeannie
 * Try speaking to Jeannie at night while she is at her house, or while she's on her way home or in the Motel Lobby.
 * The option to tell Jeannie to go to the dinosaur disappears after retrieving the bill of sale from the safe.
 * This can be worked around by telling her to go to the dinosaur first, then returnand retrieve the bill of sale.
 * If you still do not get the option to tell Jeannie to go to the dinosaur, wait until 11:30PM when she walks outside.
 * If you talk to No-Bark Noonan and before meeting for the first time Boone he will confront you as if you already know him, skipping dialogue and interaction with the character that would have been available before you accepted the quest.
 * If you ask the wrong person to go in front of the dinosaur then talk to them about something else,they will become stuck and they do not return to their original location. After this you are no longer able to take Jeannie May Crawford in front of the dino, rendering the quest broken. (Confirmed on PS3, however, the character did not get stuck. No fix found yet)
 * For some reason, Boone would not shoot the person sent to the front of the dinosaur with the beret equipped, no matter who it was. Apparently, the only way this was worked around is to shoot at Boone for his attention, then hide behind the person in front of the dinosaur.
 * Starting the quest without first talking to the hotel manager about heading over to the gift shop will cause Cliff to not take over as hotel manager and so maing it impossible to access the hotel room. (unless you get the key before having her executed) -- Disputed: I was able to loot the key from her body after Boone killed her.
 * Speaking to Boone, during the quest, as he's heading to the sniper post will cause him to become stuck. Making it impossible to complete the quest since Boone will no longer be able to shoot someone.
 * Sometimes, if you send Jeannie but don't wear the beret, you may not be able anymore to repeat the operation. However, Boone will consider quest as finished if you speak to him, so you can have it as a companion while Jeannie is still alive.
 * On rare occasions, NPC's (Jeannie's?) AI walking script will stop working. As a workaround, the player must push the NPC to the location to complete the quest. --Confirmed
 * The best way is talk to Jeannie outside when she leaves around midnight. I always get the option to follow.
 * Binding Boone's Beret to a Directional Pad key may result in a console crash. (CONFIRMED)
 * obtaining the evidence before talking to No-Bark will result in a quest completion for the optional objectives.
 * Sometimes the evidence will not appear in the safe, halting your progress unless high enough speech is available to convince Boone without it.
 * Sometimes upon trying to complete the quest, there will be no chat option to show Boone the Bill of Sale, rendering the companion recruitment broken.
 * After completing the quest Boone's beret will remain in your inventory.

Behind the Scenes
The quest's name, like all the companion quest names, is a reference to an old crooner song "One For My Baby (and One More For the Road)" by Harold Arlen and Johnny Mercer. It was popularized by Frank Sinatra, Dean Martin, Sammy Davis, Jr., and Billie Holiday.