Both Marion Cotillard and Joaquin Phoenix attended a screening of "The Immigrant" in NYC last night -- but this girl is the one everyone's talking about this morning.
Don't know who she is? Don't worry, you're not alone.
Her name is Jazmin Grace Grimaldi ... and she's the granddaughter of the late Grace Kelly, aka Princess Grace of Monaco.
The 22-year-old with the unfortunate sweat stain hit the red carpet on Tuesday night in NYC for reasons unknown, giving us a rare look at one of the gorgeous actress' descendants.
Jazmin is the illegitimate daughter of Prince Albert and former waitress Tamara Rotolo, who gave birth to their daughter in 1991. Albert didn't admit he was the father publicly until 2006.
Grimaldi is one of two illegitimate kids for the Prince and neither one of them is in the line of succession for the throne.
Jazmin is currently attending Fordham University in New York.
