Yes it is true. See, I was adopted at about 11 months. The first photos of me at that age show an immense baby. You can hardly believe my mother, a normal sized woman, can even hold me.
I knew I'd been a small baby per my birth certificate. It wasn't until a couple years ago, when I met my birth mother, that I learned about the incubator thing. I guess you could say she fattened me up for market. She didn't put me up right away because my birth father was ambivalent, so she thought they might have a future together. It was only when he disappeared into the army that she realized, no. Then she put me up.
The fattening thing, well remember there was no such thing as a too-fat baby back then. I reckon she responded to my small size by feeding the hell out of me.
And yes, the weight has remained. Mostly not to the level of obesity, but I've had plenty of yo yo dieting, etc. I wrote about it more in Why So Much Nutrition Writing Is Useless.