Tiel mourns brother - LOUDLY!!!

Hi, it's night now and the birds are covered and blessedly quiet... Our male 'tiel Gilbird has been shrieking off and on all day, for much of the last week, since his "brother" BooBoo died. We bought them at the same time. The breeder was having trouble finding homes for them, so she offered us 2 for one, so to speak. Gil was very funny and active and hubby and son, liked him, and I found Boo. He was the softest cockatiel I've ever felt, and when I took him out of his cage the first thing he wanted to do was bite my glasses. Unfortunately, Gil became very cage-bound, and anytime we took Boo out he would start shrieking until Boo was back in his cage. They didn't share after Gil bit a hole in Boo's beak!
Anyway, Sunday am Boo was down on the floor of his cage, and he was gone within about 5 or 6 hours. I hoped that having seen that Boo was dead, when we took him out of the cage, would make things easier, but it doesn't seem to have helped. One thing that has made things worse is that hubby took Boo's cage away to clean it really well, so that's gone.
We're trying: moving his cage closer to one of our other birds, a Meyers, so there's someone closer to him; giving him a mirror; varying levels of covering during the day ( he's always wanted partial cover). I almost want to just go buy another 'tiel to be his pal (and my new baby)...
Any ideas??? Suggestions for good brands of earplugs?
-Mary (missing Boo in many ways)

Can you put the empty cage back up in the same place where it would have been
leave it there for a week or so and let him realise that no ones home so to speak
each day move it a little bit more away from him till over the course of a week or 2 you can completly remove the cage without much issue

you can do this by moving the cage away from
him in his current spot or by moving him away and towards your myers
choice is yours
I think once he has time to realise that his friend has passed on he should be ok

If not then perhaps try another teil
don't expect any miricals though just cause it's another teil dosent mean he'll like it or that it will solve the problem

Other members hopefully have more advise but this is what I would do
just my opinion