updated 01/12/2010 AT 7:00 AM ET
•originally published 01/12/2010 AT 8:30 AM ET
It’s been more than two decades since Brittny Gastineau’s father Mark, the legendary New York Jets player, left Brittny’s mom Lisa for actress Brigitte Nielsen. But it wasn’t until last week that Brittny met the fruit of that union: her half-brother Killian Marcus Gastineau, who’s now 20.
Brittny had never before seen or spoken to Killian, who lives in Italy and works at a wine and champagne company. “I’ve always known I have a half-brother, I was told as a kid, but he was totally off the radar. It was like he didn’t exist,” Brittny tells PEOPLE.
But Brittny’s mom bumped into Nielsen at Ivana Trump’s wedding last year, and they exchanged phone numbers – and, surprisingly, pleasantries. Then, last week, Nielsen “texted my mom and said Marcus is in town and he’d love to meet me,” says Brittny.
So, Brittny and her mother met Nielsen and her husband Mattia Dessi, along with Marcus, for dinner at Il Pastaio in Beverly Hills.
“It was very weird and surreal,” says Brittny, who hasn’t been in touch with her father for several years. “I didn’t cry. I’m too tough to cry. But we hugged, we talked about old stories. He said he watched Gastineau Girls in Italy, so he knew what I looked like.”