Mom gives birth naturally to 13-pound baby boy: 'I was in shock!'

An Australian mom who always wanted a "little fat baby" got her wish when she gave birth to a 13-pound infant.

Natashia Corrigan's giant baby boy came into the world in January, an arrival that left her stunned.

Read: Holy Ultrasound! Christ on the Cross Appears In Mom's Sonogram

"I was induced with my other pregnancies so with this one I wanted to see what it was like going into labor naturally," Corrigan told InsideEdition.com. "We knew he was going to be bigger because I carried big, but we assumed he'd be no bigger than 11 pounds."

See photos of Corrigan and Brian Jr.:

So when Corrigan, who had no medical problems during pregnancy, was informed of Brian Jr.'s weight, she was flabbergasted.

"When the nurse told us his weight I was in shock!" Corrigan exclaimed. "She said he was 6.06 kilos so I had to go on my phone to check the weight conversion and when I realized his weight in pounds I couldn't believe it."

Read: Mom Says Baby Didn't Really Clap to Music During Ultrasound

Corrigan, whose previous babies were normal weight, said she brought newborn-sized clothing to dress her son but ended up having to dress him in clothes that would normally fit a child 6-12 months old.

Now, at 11 weeks, Corrigan said he's still in the top percentile for baby weight.

"He's grown longer, faster and heavier," Corrigan said.

Read: Why These Retired Women Spend Time Cuddling With Babies