At the time, in 1997, the message was still new, but it was everywhere. After decades of watching helplessly as thousands of healthy babies succumbed to SIDS, the United States government was eager to tout back-sleeping as an easy prevention technique that actually worked. The National Institutes of Health launched a public health campaign to get out the word in 1994; within three years, federal funding had grown to $1.1 million a year.
And so every night, every nap, Marin made sure that her baby boy slept on his back. Even when he wasn't sleeping, even when she was there to play with him, he was on his back.
"I was afraid," she says. "You don't want your baby to die of SIDS."
By the time the boy, whom she named Marin Acevedo, was six months old, the right side of the back of his skull had gone flat. Meanwhile, the left side bulged out a bit, making his left ear noticeably higher than the right.
The boy's mother wasn't the only one worried about it. "Everyone in my family said, 'His head is flat in the back!'" she says, sighing. "Family, they'll tell you straight out."
Marin had read about treatments for misshapen heads. She knew soft-shell helmets, for example, could round out flattened areas. But when she took the information to her pediatrician, he assured her that the baby's head would even out on its own.
Now Acevedo is 7. His head is still flat on the right side, and his left ear is still higher. He wears his hair long, but his mother worries what will happen when he decides he wants it shorter.
She sent a desperate e-mail from her home in Brooklyn, New York, to the nation's leading helmet provider, in Tempe. Timothy Littlefield, vice president of Cranial Technologies, wrote back to tell her it was too late: Helmeting only works while a baby's head is still in its greatest growth stage, before the child turns 16 months old.
"I get angry about it," Marin says. "Not that he's so terribly deformed, but that it's something that could have been prevented."
After all, by the time Acevedo was born, physicians had reported in medical journals that skull deformities like his were reaching "epidemic" proportions.
The same doctors observed that the back-sleeping position -- urged to protect babies from Sudden Infant Death Syndrome -- was causing the problem. They'd written studies about the benefit of helmets and the importance of rotating the position of babies' heads to prevent the problem in the first place.
But most pediatricians take their cues from the American Academy of Pediatrics. And the Academy failed to acknowledge the problem for years, much less tell parents about treatment. The federally funded National Institute for Child Health and Development, too, spent millions urging parents to sleep their babies on their backs, all the while insisting that the deformities just go away on their own.
As kids like Marin Acevedo make clear, that simply isn't true.
These kids are now going to school, and some are finding that they can't play football because the team's helmets don't fit. Or they can't find a bike helmet that's big enough. Some parents look into surgery. One New Jersey couple sued their pediatrician for failing to suggest treatment for their son when he was an infant; the jury looked at the boy for 15 minutes and ordered a $2 million verdict.
Parents concede that the problems are mostly cosmetic. But in this appearance-obsessed society, it's hard to pretend that aesthetics don't matter: Study after study has shown that attractive people have an advantage in life. As Barbara Marin admits, she's angry at herself because she could have knocked down one hurdle facing her son -- but didn't.
And now, for the first time, studies are suggesting that the problems may be more than a question of beauty: Even if their deformities are treated, new research indicates that babies with misshapen heads are more likely to have developmental delays and need extra help as they get older.
Still, prominent members of the Academy insist that there's no cause for concern. Leaders at the National Institute for Child Health and Development say the same thing.
They seem petrified that, by acknowledging the deformities, parents will freak out and put the kids right back on their stomachs.
But in the end, their refusal to address the problem may be achieving the very result they'd hoped to avoid.