Sleeping with a silver star necklace is normally safe because silver is a reasonably soft and non-reactive metal. To prevent tangling or breaking, it's a good idea to remove any gold or silver jewellery, particularly necklaces, before going to bed. In addition, some individuals could find it challenging to fall asleep wearing a necklace. If the necklace contains delicate or complicated pieces, it is more likely to be damaged while sleeping. Overall, while it is not dangerous, it is best to remove silver necklaces before going to bed for both comfort and jewellery preservation.