Is My Senegal Plucking??

[Socialseagull]

Short hhistory of the bird and environment. bird is a rescue I have had for about 4 yrs. Never witnessed a all over molt, just a few (less than 5) over a time of 3 to 4 weeks in the Summer here in MD. I am in a condo.The unit above has a child with obsessive compulsive disorder that is 6+ yrs old. He is of course fixated on my parrots. First it was the cockatoo. All began 3 yrs ago. He playes tape recorded screaming of the cockatoo, and also just recently..the senegal. He stands above where he thinks the cages are and drops heavy objects, jumps up and down, screams, calls the birds by name....
Just think hell on earth and you are close. Yes above me knows. No they do not care. Yes they like harassing my animals. No animal control can't do anything about it. No I can't afford to move. My birds no longer make calls to me or each other. I whisper to them and try to move the cages around. The first alarm scream and the kid homes in. Within a 4 day period this Senegal has plucked all feathers from a wing-body joint area, and down that creviss all the way half down the back. The skin appears red. I am taking her to the vet, but am curious if anyone has had such a "sudden" plucker?
My cockatoo pulls out her "wingpit" feathers and side feathers when molting, but the Senegal has done this removal only on her left side. No age known. There was some pattern changes over the 4 yrs. But the eyes have always been yellow(bright as the belly!).No green feathers near the vent or under the tail so took it as female. Pied head now with many golden speckles on the face and neck. Any ideas or personal stories welcome.

[Harpmaker]

Sounds awful!

Soundproofing? Maybe a dropped ceiling with acoustic insulation in one room. Pricey, but it's all I can think of, short of some options you've already rejected.

Good luck!

Edited to add: I assumed you have had your avian vet eliminate physical reasons for plucking, but if you haven't, do that first. Cheaper and more effective than construction.

[Pajarita]

Sometimes, Giardiasis causes parrots to pluck under their wings and on their shoulders. Please ask your vet to check for it, just in case.

I would put in a complaint about excessive noise with the management - but I would not mention the parrots at all. I would just say that heavy objects are dropped suddenly much too often and that maybe a wall-to-wall carpet with thick underpadding is needed.