A mother in Australia knew she was expecting a big baby, but even she was shocked when she realized how much her new bundle of joy weighed.

Natashia Corrigan gave birth in January to Brian, who weighed a whopping 13.4 pounds, according to News 7.

Even more amazing, Corrigan managed the difficult delivery with only the help of nitrous oxide, also known as laughing gas. She chose to go the more natural route by not receiving an epidural.

Corrigan said on Facebook that she thought Brian would weigh 11 pounds at most. According to News 7, the baby weighed 9 pounds at the 36-week mark of Corrigan's pregnancy.

Corrigan, Brian and the family are doing well. Corrigan has two other children, both girls, who didn't tip the scales like their baby brother did.