At a certain point, if Lily Bowen is the active Companion, the Courier may begin to hear a recording of children greeting their grandmother. This signals the start of Lily's unmarked quest. The playback of the recording of her grandchildren occurs when the following conditions are all satisfied:
The Courier has talked to Lily about Leo and replied about it (generally available in her typical dialogue tree asking her about herself)
The Courier witnessed her suffer a psychotic break during combat (health is reduced to about half or below, the Courier can cause her health to be reduced to half or below and does not have to be in combat and it causes the same outcome) and talked with her about it
You have witnessed her taking her medicine and talked to her about it (new dialogue option available in dialogue tree asking her about herself) She says "Medicine Time", "Hush Leo; it's medicine time now" or "Grandma has to take her pills now, Dearie" when she takes her medicine.
To complete the quest, the Courier must listen to the entire recording and then open a dialogue with Lily. After asking her several questions and discovering that she has only been taking half the recommended dosage of her medicine, the Courier is given three choices:
Recommend that Lily begin taking the complete dosage. If this option is chosen, Lily will stop suffering psychotic breaks altogether, but will suffer some permanent combat penalties - these remain in effect regardless of her mental state. (Melee Weapons skill set to 60)
Recommend that Lily continue to take half her dosage. If this option is chosen, she will continue to suffer psychotic breaks when she is reduced to one-quarter HP, but will now calm herself immediately if the player enters Sneak mode.
Recommend that Lily stop taking her medicine altogether. If this option is chosen, Lily will now suffer psychotic breaks when reduced to half HP, but will gain several permanent stat bonuses - these remain in effect regardless of her mental state. (Melee Weapons skill set to 100)
The Courier's choice will also have an effect on which game ending Lily receives.
Some quest stages can be started through the use of console commands:
To start the medicine dialogue, enter set "160267".ftimer to -1 and set "160267".bMedicineTime to 1
To start the holotape dialogue, enter set "160267".fresttimer to 1 and set "160267".bdoonce to 1
To start the psychotic break dialogue, enter set "13e510".bPsychoticBreak to 1. This won't make Lily enter a psychotic break, it will however unlock the dialogue option about it and allow for the quest to proceed normally.
↑Quest name from Fallout: New Vegas Official Game Guide
A Bit of Slap and Tickle ·A Final Plan for Esteban ·Access Powers ·All Fired Up! ·An Ear to the Ground ·Andy and Charlie ·Arachnophobia ·Arizona Scavenger ·Barton the Fink ·Bear Necessities ·Big Winner (Atomic Wrangler, The Gomorrah, The Tops, Ultra-Luxe, Vikki & Vance) ·Bounty Killer (I, II) ·Brotherhood Bond (I, II) ·Caching in at the Cove ·Cajoling a Cudgel ·Claws Mended ·Claws Out ·Dealing with Contreras ·Defacing the Humble Stone ·Democracy Inaction ·Don't Poke at the Bear! ·Eddie's Emissary ·Exhumin' Nature ·Fight Night ·Flogging a Dead Corpse ·Friend of the Followers ·Gland for Some Home Cooking ·Harder, Better, Faster, Stronger ·Hat's Entertainment ·Help for Halford ·Hidden Valley computer virus ·Highway to the Danger Zone (I, II) ·Honorary Rocketeer ·I Love Bananas ·Iron and Stealing ·Keith's Caravan Charade ·Laurifer Gladiator ·Lenk's Bad Debts ·Lily and Leo ·Long-Term Care ·Malleable Mini Boomer Minds ·Maud's Muggers ·Meeting an Equal ·Missing a Few Missiles ·Most Wanted ·Not Worth a Hill of Corn and Beans ·Old School Ghoul · A Pair of Dead Desperados (I, II) ·Papers, Please ·Pistol Packing ·Playing on the Old Joana ·Poor Meat Never Makes Good Soup ·Powder to the People ·Power to the People ·Razzle Dazzle! ·Reach for the Sky, Mister! ·Rest and Resupply ·Ringo's Caravan Rules ·Rotface's Loose Lips ·Saving (or Savaging) Sergeant Teddy ·The Screams of Brahmin ·Silus Treatment ·Short-Term Treatment ·Smooth-Talking Criminal ·The Star Showdown ·Strategic Nuclear Moose ·Straus Calls ·Strip Search ·Suits You, Sarah ·Tags of Our Fallen ·A Team of Moronic Mercenaries ·Thought for the Day ·Tourist Traipse ·Trudy's Radio Repair ·A Trusted Aide ·Useless Baubles or Fancy Trinkets? ·We Must Stop Beating Like This ·We Must Stop Meeting Like This ·Wind-Brahmin Wrangler ·You Gotta Break Out a Few Eggs ·You Make Me Feel Like a Woman
Sierra Madre Grand Opening! · Find Collars (8: "Dog", 12: Christine, 14: Dean Domino) ·Fires in the Sky ·Strike Up the Band ·Mixed Signals ·Trigger the Gala Event ·Put the Beast Down ·Last Luxuries ·Curtain Call at the Tampico ·Heist of the Centuries ·Big Winner, Sierra Madre
A Family Affair ·Arrival at Zion ·Bighorners of the Eastern Virgin ·Chaos in Zion ·Civilized Man's Burden ·Crush the White Legs ·Deliverer of Sorrows ·Departing Paradise ·Flight from Zion ·Gathering Storms ·Gone Fishin' ·Happy Trails Expedition ·Prisoners of War ·Retake the Bridge ·River Monsters ·Rite of Passage ·Roadside Attraction ·Sanctity of the Dead ·The Advance Scouts ·The Treacherous Road ·The Grand Staircase ·Tourist Trap
All My Friends Have Off Switches ·A Brain's Best Friend ·Coming Out of Her Shell ·Field Research ·He Came... And Went ·Influencing People ·Midnight Science Fiction Feature! ·Old World Blues ·On the Same Wavelength ·Picking Your Brains ·Project X-13 ·Sonic Emitter Upgrade ·Welcome to the Big Empty ·What's in a Name? ·When Visitors Attack! ·X-2: Strange Transmissions! ·X-8 Data Retrieval Test ·X-8: High School Horror! ·X-13: Attack of the Infiltrator!