Bellhart Bellhart is offline

Cloth trainers/diapers also make sense then, since those are reusable.
Restraint harness also works just fine, and I can see how it could be utilized.

However I'm really not sure they should begin the journey out in the wild, especially not with Ellie already having weakened control. The whole idea, at least as I imagined it, was centered around them having to trade Ellie's freedom, self-respect and possibly continence, for the safety of the Firefly hospital and the hope to cure the infection by developing a vaccine from her immunity, and letting her go when that's done. (btw, technically, strictly in medical terms, she's not immune, she's a carrier, someone who's infected, but asymptomatic, and can still pass on the infection) - and that they have that strong bond to help them through this, from the experiences of having saved each other's lives.
Plus, continence is something Ellie should have at the start so she has to deal with losing it, not being used to needing diapers from the very start.
(Also, I'm not -that- well versed in the game's universe and plot, so I'd be at a disadvantage outside)

Definitely mandatory for nighttime. Probably some pull-ups or cloth diapers/training pants for good measure during daytime (think about something similar to the Potty Patty training pants) so she could at least feel like she's wearing something closer to normal underwear.
Or she could be fully diapered 24/7, you decide. Not having to be diapered all the time means she doesn't get used to them, so when she has to wear them again, the embarrassment factor doesn't go away :P

Well, I thought she would not spend all her day always tied down, only nighttime and when she's not with Joel. I assumed even the Fireflies have some actual experts at hand who don't underestimate the importance of a trusted father figure to help maintain her mental and physical health, as well as keeping her in check. She could be only wearing the muzzle, mittens and booties by default and wear normal pyjamas or nightie with them, maybe as standalone restraints, maybe as part of clothing like a straitjacket, onesie or jammies, and during daytime the restraints could be light, like a basic harness tethered to the wall or her bed, to make sure she cannot reach a door or window, and some short straps between her ankle cuffs and connecting her upper arm and wrists to the harness to limit but not completely eliminate her movement

Asking me? You are the expert in The Last of Us and it was your idea... You take point on this one :P

Have you been having a good summer?

Yes, I think we should

Yes, I might be interested. Also, of course I was feeling it, we barely started that one XD

BTW, we had another RPG you requested, the diapered prison school reformatory? I wonder if you simply forgot or lost interest (I would understand both)

So, like wearing a muzzle, mittens and booties to prevent her from biting, scratching or any other means to transfer the infection, maybe a harness or bed restraints knowing her agility and unpredictability to prevent escape, and instead of having half her brain removed, there are only a few biopsies for small tissue samples and blood tests for antibodies? (which, BTW, actually makes more sense than killing the only live specimen you have)
The brain biopsy might even cause some minor continence issues like bedwetting or weakened bladder control (occasional, like a side effect of sedation, or temporary, due to minor, recoverable brain damage due to the biopsy, that shouldn't last for more than a few days or a week)

Considering that I'll probably never play it, spoil away.