Sofia Vergara Poses in Thong Bikini from Behind Next to Hottie Niece

Sofia Vergara's got a fun game for folks to play at home during quarantine -- it's a bit of a thirst trap, but with a bootyful twist: whose behind is whose?

The Colombian actress posted a lovely photo this weekend showing herself and her niece, Claudia, rocking two-piece thong bikinis and looking over a balcony at what appears to be Sofia's home. You can't see either of their faces -- but that wasn't the point of Sofia's post.

Sofia wrote of the aunt-niece duo in Spanish, "Modelo viejo del 72 y modelo nuevo del 92 😂😂😂😂 #alwaystwinning @cdvergara ❤️❤️❤️🌝🌝🌝." That translates to "old model from '72 and new model from '92."

BTW, she also posted a photo of Claudia from the front, bending over to make a burger, with uncle Joe Manganiello beside her working on his own grub. She's a lookalike from the side as well, but(t) as far as that first photo goes, it's actually SUPER hard to tell for sure who's who, no?

Anyway, just for funsies ... here's another look at the same pic in black and white -- only now it's coming from Claudia, who also seems to be in on the same guess-who game.

She writes, "Same same, but different ... cual es cual? 😂" Which is which, indeed. We could play this all day!!!