The pair is "really cute together," a source close to the stars told Page Six.
According to the publication, the young couple showed some hot PDA this weekend, "smooching all over Montauk" and the Hamptons.
The blooming romance comes just two months after 25-year-old Agdal was seen wrapped around the arms of now ex Leonardo DiCaprio, 42.
As RadarOnline.com readers know, the couple called it quits after DiCaprio was allegedly caught texting and meeting with British babe Roxy Horner, 25, behind Agdal's back.
"Leo has been texting Roxy in the past month, even though everyone thinks Nina is his girlfriend," an insider told RadarOnline.com. "They've been friends for years, but he has always wanted more."
While Agdal and the Shutter Island actor lasted almost a year, sources say she and Brinkley-Cook are already getting "serious."
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Do you think Agdal is better off with Brinkley-Cook than she was with DiCaprio? Let us know in the comments below.
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