What happened to Judith?

From Examiner.com

Some fans noticed that Tyreese had some sort of carrier on his back. Inside it resembled a baby, although the shot of it wasn't close up. This caused some confusion with fans on whether baby Judith was dead or alive.

On "The Talking Dead," the subject of baby Judith was brought up and it was confirmed that the infant is alive and well. She was in the carrier that was on Tyreese's back.

If she had died, it would make sense why they wouldn't show her at all. The death of two children is hard enough for one episode, although one of them was a danger to survivors everywhere. But seeing the death of a baby would be too much for many viewers. Not only that, but fans are looking forward to Rick and Carl finding out that Judy is alive after all.

From a different Examiner.com article referencing the Talking Dead chat show:

On March 16, "The Talking Dead" confirmed the fate of the baby.

They didn't show Judith at the end of the episode when Carol and Tyreese were walking away, but if you paid attention you could tell she was there. He was wearing a yellow pouch on his back. Paying attention to it you could tell that it was Judith and could see her head with a hood on it.

On "The Talking Dead," it was confirmed that yes that was Judith on his back.

From someone who watched the show:

The baby was in a "papoose" on Tyrese's back. There was no need to kill the baby, she was alive and well when Tyrese and Carol returned to find Lizzy covered in Mika's blood, and they would have made sure Judith was well protected from Lizzy afterwards.