The Curly Sue star delivered baby boy Mason Blase Autenrieth, who weighed in at seven pounds (3.2 kilograms).
She kept her Twitter.com followers updated before going into labour, writing, ""Hour 16. No baby. He's prob (probably) changing his outfit 400 times like his mother... Mason is tardy for the party.""
The new arrival is the first child for Porter and her husband Brian Autenrieth, who she married in March (12).