Thanks so much for sharing your lovely story. I'm not a particularly religious person myself (in the sense of believing in any one orthodox religion), but I firmly believe that there are mysteries to life -- and death -- that we will never truly understand.
In your case, your brother was speaking to you, lovingly and gently, in the only way available to him.
My middle brother was very close to our mom. When he passed away suddenly about 5 years ago, she ended up keeping his wristwatch on top of her microwave. At first the alarm would go off at 3:16 every afternoon (none of us knew why he'd set that time). As time went by, it still would ring, but just every now and again.
When it did, it was ALWAYS when she was feeling particularly blue or lonely, or when her polymyalgia rheumatica was in its active stage (a horrible and extremely painful disease). She took comfort in hearing it chime, knowing that Rick was there with her.
She passed away herself this past October. We put a new battery in the watch and I placed it, with her ashes, in the little niche right next to his. I like to think that they both would have liked that.
Thanks again for sharing.........