It's actually not as big an issue as it first sounds. First rinse them with tap to get rid of as much bleach off as possible, then soak them in a bucket with dechlorinated / treated water from your de-chlorinator, which will neutralize the chlorine for 1/2hr to hr at most ... just to make sure.
Many members bleach ornaments to ensure any unwanted microbes are killed.
I guess this is a case where you can thank your sister for caring enough to bleach your ornaments AND for killing off the BB that lived on the surface of the ornaments. Fortnuately, the majority of BB live in the filter media so I don't think you'll have a mini-cycle.
75g Planted Barbs Denison, BlackRuby, Tiger, Albino Tiger, Green Tiger, Cherry, Gold, Checkered, Odessa.
NonBarbs Cardinal, Neon, RummyNose, Bloodfin Tetras, Z. Danios. 1RTS. Amano, Bamboo, Ghost & RCS. 20g Long Shrimp Tank RCS, Tiger, Amano.