02/07/2014 AT 04:30 PM EST
When Sammisano Otuhiva was born in San Francisco in August, the hospital staff were making bets on how much the supersize newborn weighed.
"The nurses were guessing 10 or 11 lbs., and the doctor guessed 14," the boy's mom, Sosefina Tagalu, tells the Huffington Post
. But when they put him on a scale, he came in at a hefty 16 lbs., 1.7 oz.
Tagalu knew her son was big but she had no idea he was a record breaker until learning about another baby, Andrew Cervantez, who made headlines
in January when his parents claimed that at 15 lbs., 2 oz., he was the largest baby ever born in California.
"My friends and family told me I needed to set the record straight," Tagalu tells the San Francisco Chronicle
The 39-year-old, who gained 110 lbs. during her pregnancy, delivered her son via Caesarean section. And he was so large that the hospital's newborn unit didn't have diapers big enough to fit him.
Now 5 months old, Sammie, as his family calls him, has continued his super growth spurt. He now weighs 25 lbs. – the average weight of an 18-month-old.
Having a supersize baby has meant that he never got to wear the baby clothes Tagalu was given at his shower. He was dressed in clothes for a 12-month-old on the day he was born and now is almost the height of his 6-year-old brother and wears large-size diapers.
Tagalu, who works as a medical assistant for a nonprofit organization, says she had to return to work three weeks early "to cover the extra cost of food and diapers."
Sammie, who started eating solid food a couple of months ago, has a massive appetite. "I feed him a bowl of [instant rice] cereal, and when it's finished he looks at me like, 'Mom, where's the rest?' " she tells the Huffington Post, adding with a laugh: "He's a handful."