Hi,
My mum is also allergic to my grey but she is also allergic to cats. Birds can bring on asthma also and from you saying tight chest I think this may be a possiblilty and maybe your mum should think about visiting the Doc.
My mum is okay around bubbles and is even going to be looking after him for a couple of weeks while i am on holiday. The only time she is affected by her allergy is when she cuddles her but she has found out that if she Piriton tablets the allergies dont rear there ugly head.
My mum is not affected by us visiting her she physically has to be with bubbles. She doesn't even have this reaction from our Cat and her feline allergies are far worse, but same again when visiting us she takes a piriton and no more allergies.
I wouldn't advise putting your grey in the garage or in any room where she will be alone. Your grey is sociable creature and would feel lonley and may develop beahavioul issues. I take bubbles outside on her lead but even on the warmest of days our lovely british weather she can be cold if there is a slight wind. Also think of how cold the garage would be at night-time and you elecy bill if you were to have it heated all night.
I found this on
http://www.theparrotsocietyuk.org/petparrot.shtmlCons - Prone to feather plucking if bored or frustrated, so needs lots of attention. Produces lots of feather dust, a white "powder-down" , which leaves a layer of dust which most house proud people would not appreciate. Also bad for asthma sufferers or anyone suffering from allergies
I seem to have rattled on a bit but I hope that this helps.