The Victoria's Secret model took to her Facebook page to reveal the moniker or her and fiance Jamie Mazur's second child, who ''stole their hearts'' when he was born in Florianopolis, Brazil, yesterday (07.05.12).
Alessandra - who also has three-year-old daughter Anja with Jamie - wrote: ''Well, the day just arrived and we couldn't be more happy!!!. Noah Phoenix was born yesterday afternoon and already stole our hearts.''
The 31-year-old Brazilian model also revealed Anja is a ''proud sister'' to Noah.
She wrote: ''Anja is a proud big sister now and we are so thankful he is with us.''
Jamie had previously taken to his twitter account to express his excitement at their new arrival shortly after his mother Michelle Mazur revealed the couple's son had been born in the South American country.
He explained: ''Welcome my son, can't wait to show u around this crazy place. (sic)''
He wrote: ''Noah Phoenix will be performing on the main stage at Coachella 2035 with special guest Thom Yorke Save the date. It should be a good show.''