There's a current thread on Etsy about whether it would be considered copying if two designers came up with close-to-identical items around the same time span. Interesting thread and several good ideas about what to do.
I created an abstract graphic design of a Bird of Paradise flower after I'd wandered around the mall one day and stopped in to a florist's shop. There was a distortion in a mirror they had on display and when I saw that Bird of Paradise flower reflected in that mirror, I knew what my design was going to be. This was a commission work, knit in Double Bed Jacquard on my electronic knitting machine. It ended up being the central portion of a wall hanging for their vacation home.
Other than the colors and the medium (hers was screen printed), I saw darned near the same thing on a pillow in a little boutique the following year and when I inquired, the shop owner told me it had been brought in by an artist the previous year! Coulda knocked me over with a feather. And this was right around the same time I was slaving over those graphs to get it 'just' right. No one had seen my work other than the original customer. I'd not even shared it with my online friends, which is unusual for me.
It can happen. To anyone. I like to *think* I'm unique in my crafting life, but if I can think of it, so can someone else.
~ Marge ~