TORONTO - A Canadian couple say it's none of the world's business to know their baby's gender despite a firestorm of criticism over their decision to keep the infant's sex a secret.

Kathy Witterick said her 4-month-old baby, Storm, should in time be able to develop its own sexual identity without having to conform to social stereotypes or bow to predetermined expectations associated with gender.

Witterick, 38, and her husband, David Stocker, 39, have faced a backlash since the couple's story first appeared in the Toronto Star last weekend.

Witterick said in an e-mail Friday that the idea that "the whole world must know what is between the baby's legs is unhealthy, unsafe and voyeuristic. We know - and we're keeping it clean, safe, healthy and private (not secret!)." She said those closest to Storm knew the infant's gender.

She and her husband have also been criticized for the way they are raising their two other children. Five-year-old Jazz and 2-year-old Kio are well aware that they're boys but have been encouraged to shun gender norms and express themselves in whatever way they wish, she said.

Witterick said Jazz had the right to choose his clothes and hairstyle and said he choose freely to wear pink despite criticism. "Jazz has a strong sense of being a boy, and he understands that his choices to wear pink and have long hair are not always acceptable to his community," she wrote.

She said an infant at four months was still learning to recognize himself or herself and it's not appropriate to force a sex on the child. She added that she and her husband had been trying to keep their children safe from a media frenzy, but said it had been difficult.

The two have been criticized for imposing ideological values on a newborn and subjecting their children to ridicule. A follow-up article in the Star documented furious reader feedback, including that the two were turning child-rearing into a social-science exercise. However, Laura Swan, a friend of Witterick's, called her a "really good mom."

Ken Zucker, the chief psychologist and head of the gender-identity service for children at Toronto's Centre for Addiction and Mental Health, said the story had caused anxiety among people who were now wondering how they became who they are. "The reason this story has gone viral and been of so much interest is because it has activated an ongoing discourse of how does a child's gender identity actually get formed," Zucker said.