Today the world's population reached seven billion. Duncan Kennedy, reporting for the BBC, spent the first few hours with that seven billionth baby — or one of the newborns that could lay claim to the title — Alice, in Australia. He spoke with her new parents about the advent of a new life in their world, and about what it's like to be the parents of a child on a 7 billion person planet. 

Scientists have found that babies can become fluent in foreign languages at an extremely fast rate; one that begins to slow down by their first birthday. What is it about the make-up of their brains as newborns that gives them this ability? Could adults train their brains to be more like the brains of babies?

Melonie Ware was a daycare provider in Georgia who was sentenced to life in prison for shaking a nine-month-old baby to death in 2004. But in a 2009 retrial, a court declared that the medical examiner's findings were insufficient, concluding that the baby most likely died because complications due to sickle-cell anemia, and acquitted Ware.

Doctors have credited hundreds of untimely infant deaths to shaken baby syndrome over the years. But more and more, medical experts are starting to doubt that baby shaking was the cause of death in certain cases. A new Frontline documentary, airing tonight on PBS stations, examines some of these cases, including Ware's. 

This year's Nobel Prize for Medicine has gone to Dr. Robert G. Edwards, an English biologist who co-developed in vitro fertilization, the revolutionary process that has allowed millions of infertile couples to have babies. It's been thirty-one years since the first test tube baby was born. We take a look at how the world has changed since then with Robin Marantz Henig, author of "Pandora's Baby: How the First Test Tube Babies Sparked the Reproductive Revolution."

We’ve all heard of single women in their thirties freezing their eggs for later use. But Gillian St. Lawrence has taken the idea somewhat further.

Gillian is thirty. She’s been happily married for nearly ten years. She and her husband, Paul St. Lawrence, both want children... just not yet. They don’t, however, want to face the potentially lower fertility rates and higher genetic disorder rates that might come if they decide to get pregnant years down the road. They’ve opted to create and freeze five embryos, which they’ll implant in ten or fifteen years, when they feel more ready.

Thousands of babies are conceived through in-vitro fertilization (IVF) each year, but 29 years ago, when Elizabeth Comeau was born, the in vitro method was considered strange and miraculous. Comeau was America's first "test-tube baby." Now, at 29 years old, she's just given birth to her own baby boy.

(Correction: an earlier version of this story referred to Comeau as the "world's first test-tube baby" - she was actually the first in the United States. Louise Brown, born in the UK in 1978, was the world's first baby conceived via IVF.)

One in eight babies in the U.S. is born prematurely. In the best case scenarios, these tiny infants grow up to live healthy lives, and maybe even become famous. Stevie Wonder, Mark Twain, Albert Einstein and Isaac Newton were all born pre-term.

But in the worst case scenarios, their early days are defined less by potential future accomplishments than by the all-out struggle to hold onto life.

Newsday film critic and Takeaway contributor, Rafer Guzman previews the weekend's most anticipated films. Robert Downey, Jr. is out to save the world in "Iron Man 2" and a new documentary looks at the lives of babies around the world.