"When children have toys that are highly realistic, it takes this control away from children and turns the child into a robot," said Diane Levin, professor of education at Wheelock College in Boston and co-author of "So Sexy So Soon: The New Sexualized Childhood and What Parents Can Do to Protect Their Kids."

Dolls that have their own stories, represent a movie character or are marketed with specific skills "take the control of play away from children ... You watch the movie [and] it tells you what your doll does," she said. Children should be a doll's writer, producer and actor.

Joan Almon, executive director of the Alliance for Childhood in Maryland, agrees that open-ended dolls are best suited for children to exercise their budding imaginations.

"Keep [the doll] very, very simple so the child's own imagination gets to fill in the blanks," she said. Even dolls with a permanent expression on their faces can limit a child's creativity. It may be difficult for children to pour their hearts out to a doll that is always smiling, she said.

Many adults aren't only asking whether highly realistic dolls are healthy for children but also if they are appropriate. Spanish toy company Berjuan debuted Bebe Gloton, which mimics breast-feeding. The doll, whose name loosely translates as "greedy baby" and is sold in Spain, comes with a halter top for the child to wear that is decorated with two flowers, which represent breasts. Bebe Gloton makes a suckling noise when its mouth comes close to the flowers.

Dolls "should allow children to be imaginative. They shouldn't have to teach a lesson and especially a lesson that children aren't going to need for 20 years," said Emie Tittnich, infant mental health specialist for early head start at the University of Pittsburgh.

Others feel a doll like Bebe can have positive attributes for a child who is expecting a new sibling.

If you're having a new baby and you want your child to understand what breast feeding is and to feel good about it ... in context, I think that makes a lot of sense, said Stevanne Auerbach, known as Dr. Toy for her expertise in children's toys and play habits. When parents of children about 3 or 4 years old are expecting another child, it's often a good idea to give young children a vinyl baby doll they can wash and care for like a baby, she said. "Anything that helps a child feel good and understand what's going on in the world around them is good."

Still, some parents don't think it's a doll's responsibility to address adult topics such as breast-feeding.

I'd "rather explain [breast-feeding] to my daughter myself when the situation arises," said Amy Merlo, a 28-year-old mother from Peters who is expecting her second child.

Dr. Levin doesn't think the idea of children pretending to breast-feed is outlandish. "If it's important to the child, they'll try to figure out a way to do it," she said.

Historically, this is how children played with dolls. If they wanted their doll baby to do or say something, they made it do it.

The "earliest dolls were a companion," said Dr. Toy, who lives in San Francisco. They were soft-bodied dolls that children regarded as friends with whom they could share secrets, she said.

Dolls remained rather simplistic until fashion dolls like Barbie debuted in 1959. "Girls got into fantasy, fashion [and became] more conscious of how the doll looked, and their play changed, too," Dr. Toy said.

Barbie also brought something else into children's lives -- lots and lots of accessories.

Other lines of dolls with their own stories and accessories followed, including American Girl in 1986.

"We're pretty disciplined in that everything we do starts with our mission to celebrate girls," said Shawn Dennis, senior vice president of marketing, design and editorial for American Girl.

It does this through its lines of historical and contemporary dolls for girls aged 8 to 12 and its bitty babies designed for 3- and 4-year-olds. Dolls come with books about their lives that teach girls lessons about honesty, compassion and responsibility, Ms. Dennis said.

Some adults and play experts, however, don't think some of these dolls and their stories are all that innocent. The American Girl doll that has caused the greatest stir in recent months is Gwen Thompson, the friend of Girl of the Year doll Chrissa Maxwell.

Chrissa and her accompanying book were released for 2009 to teach children about bullying. Gwen, a shy girl, is a victim of bullying in Chrissa's storybook. Readers also learn that Gwen and her mother were homeless for a while after Gwen's father left them.

This trait has caused some child play experts and parents to wonder if it is fitting for children to play with a homeless doll -- especially one that costs $95.

"The only reason to have such a thing would be to raise money to help the homeless," Dr. Toy said. "If they are not doing and not providing homeless children with toys ... I don't think it's right ... I think it's the wrong approach."

"Let little girls be little girls," Monica Craig, 36, of South Hills, said about dolls that try to grapple with such serious topics.

But American Girl never marketed Gwen as a homeless doll, Ms. Dennis said. "We didn't design that as a main focus."

The company has received "thousands of letters from girls and moms talking about how positive reading the book was," Ms. Dennis said.

Regardless of her popularity, Gwen is going away at the end of the year when a new Girl of the Year and her friends are introduced for 2010.

American Girl dolls that can be designed to have the same skin, hair and eye color as a child also have caused concern for some.

"What's the purpose?" Dr. Levin said. "What is the purpose other than feeding narcissism?"

Designing dolls that are DNA replicas of children is not a focus for American Girl, Ms. Dennis said. "It's about [offering] a breadth of options."

While some worry that dolls are becoming too real, others are upset that other lines of dolls don't look real enough -- especially those meant to portray different races and ethnicities.

Many have lauded Mattel's new Princess Tiana doll that is modeled after the African-American princess in Disney's "Princess and the Frog," but the toymaker's new So In Style line of black dolls has drawn criticism because many say they look like they're simply Caucasian Barbies with darker skin. "Children should have toys that they see in their environments so certainly having dolls that are representative of different minorities or different cultural groups are very appropriate and actually should be essential," Ms. Tittnich said. "I certainly don't think that we should just take white dolls and just recolor them and say that's a representative. I think if they're making dolls that are portraying a race they should at least have some major features or major characteristics of that race."

Mattel sought input from notable African-American women, such as Cookie Johnson, wife of former basketball player Magic Johnson, and tried to design dolls that featured wider noses, varied skin tones and more defined cheekbones. Despite these efforts, many felt the line fell short.

Mattel plans to add on to the So In Style line in 2010 to address some of these complaints.

No matter how hard they try, toy companies know they can't begin to please everyone.

"As a company, we choose not to think in terms of, 'Oh, we have to make this realistic,' " said Bette Holtzman, vice president of parent and family advocacy for Golderberger, which produces dolls for children younger than 3. "Children and babies aren't the ones who notice this ... it's the parents you have to please here."

And at the end of the day, it's also parents who are left to decide what type of doll is best for their children.

"Each family is a mini-culture," said Diego Chaves-Gnecco, developmental-behavioral pediatrician at Children's Hospital of Pittsburgh of UPMC, "so it is really difficult to say what it is right for each mini-culture."