Sure. Maybe the baby grew due to the extreme swings in barometric pressure present when living in a hurricane path month in and month out and the inevitable effects said swings have on the placenta.
What??? 
Mazel Tov on the baby, sounds like she’s doing great. I wasn’t breastfed. I have weight issues and have my entire life ( I’m 43 ).
My mom had 6 kids.
I was baby #5, and wieghed about 5 1/2 lbs. My brother, baby #6, weighed 12lb 13 oz!
My mom had GD, and I think she managed her diabetes herself with baby #6 (we were living overseas, and I understand from the older sibs that she let me give her her insulin shots when I was 4 years old!). He did suffer some common problems of large and diabetic babies and has permanent brachial plexus palsy.
I had two small babies myself- a 5 pounder and a 1 1/2 pounder. Both are average sized kids (yay).
Did you, by chance, give birth in a popular tv sitcom? Giving birth to 3 month-old looking babies is pretty common under those circumstances.