Babies can now say things like "milk," "more" and "all done" — and that's before they've even learned to talk.

Baby sign language (search), a trend popularized by the baby in "Meet the Fockers" (search) and "Will & Grace" star Debra Messing (search), is becoming increasingly common in homes, child care centers and preschools as a way to teach toddlers how to communicate before they have the motor skills to form words.

"Babies' minds work a lot better than their mouths," said Linda Acredolo, a pioneer in the field of infant sign language, a retired professor at the University of California at Davis and the co-author of "Baby Signs" (search). "They know what they want, what they feel and what they remember long before they can say the words."

That's because the motor functions needed to make signs using the hands and other parts of the body are a lot more basic than the complex skills needed to pronounce sounds and form words and sentences.

But just how many mothers and fathers are actually teaching sign language to their small children — whether or not they saw "Meet the Fockers" — isn't clear.

"I don't know how many parents are actually doing it, in the midst of all the other things parents have to do," said Patty Onderko, senior editor at Babytalk magazine (search). "We haven't written about it because we don't want them to feel guilty or pressured."

Acredolo's research — which she began on her own daughter in the early 1980s after the baby started making up signs to communicate with her parents — has shown that children who use the nonverbal language first generally begin speaking at a younger age.

"We found that the signing kids were benefiting from the signing," she said. "They were in fact learning to talk earlier rather than later."

Those findings helped alleviate fears that sign language would make babies verbally lazy and delay their speech development. Kids usually don't begin speaking until after their first birthday — and often not until the age of 18 months or later, since the motor skills needed for speech don't fully develop until then. They can typically learn to sign as early as 7 or 8 months old.

The key, said Acredolo, is to repeat the word while teaching the child the sign for it. She likened it to crawling before walking, which doesn't postpone the age at which children take those first steps.

"When a baby signs, it helps them get up on their verbal legs," she said. "Signing is to crawling as talking is to walking."

Acredolo and research partner Susan Goodwyn published the book "Baby Signs" in 1996, which incorporates American Sign Language (search) signs and gestures that parents and babies have made up. They've also opened the Baby Signs Institute and have a DVD and other products.

Later studies by the pair showed that children who learned sign language had higher IQs when they were 8 years old. Acredolo said the nonverbal form of communication helps small children for a number of reasons.

"It allows babies to pick the topic of conversation, and when babies pick the topic, they learn more of the words," she said. "Another reason is that signing just excites babies about communicating. ... [And] successful signing creates brain circuitry that will then support the words coming along."

But with everything else today's parents have to juggle, incorporating yet another developmental activity is just too much for some to fit in.

One working mother of a 6-month-old baby boy said that while she finds infant sign language interesting, she has no plans to teach it to her son.

"There's no way I would have time to do that," said Helga Foulk, 33, an engineer from Ambler, Pa. "He is going to learn how to speak pretty soon anyway, so I'm not sure how much of a difference getting him to communicate a couple of months earlier would make."

In "Meet the Fockers," Robert De Niro's character is shown drilling the toddler in the film — actually played by twin boys — to learn gestures using the "Sign With Your Baby" (search) book by Dr. Joseph Garcia, which advocates using only existing ASL signs.

The program starts off with three basic signs: "milk" (made by squeezing the hand into a fist repeatedly), "more" (made by pressing the fingertips and thumb of each hand together and then tapping the two hands against each other at the fingertips) and "eat" (made by pressing the fingers and thumb of one hand together and then touching the mouth several times with that hand).

It generally takes two to eight weeks of consistent teaching for the child to learn to sign back, according to Sign2Me, the company that sells the "Sign With Your Baby" book, DVD and other products.

The babies in "Meet the Fockers" had already learned to sign before they were chosen for the movie. That plus director Jay Roach's own child's experience with sign language led to the inclusion of the practice in the film, said Sign2Me sales and marketing director Vincent Kiteley.

"That movie has done a great service to the market as a whole," said Kiteley.

Industries targeting parents of babies noticed that buzz about the trend skyrocketed after the release of "Meet the Fockers" last December.

"We got so many letters from readers asking about it and so many pitches from writers wanting to write about it," said Babytalk's Onderko. "Definitely there was increased interest."

And some celebrities have jumped on the bandwagon. Shortly after the movie came out, Messing of "Will & Grace" said her young son was learning to sign.

Kiteley said his company confirmed the actress is using the "Sign With Your Baby" program, and believes other stars like Julia Roberts (search) and "The View" host Elisabeth Hasselbeck (search) are, too.

But the trend is not limited to Hollywood. The babies of some ordinary parents are also learning to sign, either at home or at their child care center or preschool.

One mother of a 16-month-old said her son, Colin, learned three signs in day care, all related to eating: "more, "all done" (made by raising both arms in the air and waving the hands) and "please" (made by holding the hand flat against the chest and moving it in a circle).

"It's a great way to help with that in-between stage of not talking at all and speaking in full sentences," said Adrianne O'Brien, 35, of West Chester, Pa. "They're at a point where they know they want something but not at a point where they can articulate to you what it is."

In fact, child development experts say that sign language cuts down on the exasperation kids feel at not being able to make themselves understood.

"The reduction in frustration is the most common benefit we hear parents telling us about," said Acredolo. "The signing helps them not to act out ... [by] biting or pushing or shoving or yelling or tantruming."

O'Brien has noticed her own baby using the signs he's learned in contexts other than eating.

"If Colin wants [more of] something and is not able to verbalize, he can transfer that from wanting more food to other situations, like wanting to read another book," said O'Brien.

And whether or not parents or child care centers decide little ones should learn sign language, the heightened awareness about the trend has taught caregivers a valuable lesson.

"Because of all the hype, they're definitely more aware that their baby does know and can communicate more than he can actually say," Onderko said. "That message is really important."