I was reading about a woman (on twitter) whose 19 yr old daughter found a distinctive earring in one part of Sydney and then days later her 13 yr old found the exact same earring in another part of Sydney. Both had picked them up and not realized they had a pair until days later. It could be that they are a popular design, but in any case still a coincidence that siblings found each separately.
Have you experienced any extraordinary coincidences?