The sister bought a toy on a solar panel - a plastic flower.
Standing on the window, crawling with blades and leaves.
Every time I see this cute thing in my head comes a picture:
a dead city in the zombie apocalypse style, broken windows, destroying buildings,
An evil silence... And only on a semi-destructed window sheet a plastic flower joyfully blossoms with its leaves.

“There will be a sweet rain” by Ray Bradbury. Everything has been invented before you :)