Mom's dream

My mother is now elderly and frail, but possesses a great independence of spirit. Her vision is failing and her world is getting smaller. She says she rarely remembers her dreams, but recently she told me of a particularly vivid one. She was in a museum with many rooms and great curving walls, but open to the sky. My brother and I were both there, about 10 years old. Lots of people were coming in, but no one was going out as there did not appear to be any exit. The museum was full of exquisite objects, absorbingly beautiful, even indescribable. When she looked around, my brother and I had gone, and she could not find us anywhere.