The proud mama wrote on Instagram: "Blessed to welcome our son, Tobias, into the world. Born June 1st, 7.9 lbs and 21" Long. He is named after his great grandpa Tobias meaning 'The goodness of God.' Adam and I so in love with our lil' guy and are stoked to share life with him! #stokedmomma."
Hamilton, who lost her arm in a shark attack in 2003 while she was surfing, shared her thoughts on parenting with one arm.
"Motherhood with one arm, I've been kind of thinking about it," she said in a video announcement of her pregnancy. "I often forget that I have one arm, but when I think about a squirming baby, changing the diaper and just me and this squirmy baby, it could be really challenging."
Happily, husband Dirks, who also surfs, will be there to help.
"I'm going to be there to support my wife and support my family," he said in the video.