Most pregnant women dream about their baby and what that baby may sound like when crying. I watched TLC's "Baby Story" many times while on bedrest with my now 6 year old daughter. She was delivered a little earlier than expected, and was only 5 lbs. and 2 oz. And small babies' cries do not sound the same as full-term or bigger babies' cries. My daughter sounded more like a farm animal than a human! When the nurses opened the nursery door, I could identify my daughter's cries from the other babies' cries...that's because she was the only one that sounded like a little lamb! No kidding!
New parents often have a hard time knowing why the baby is crying. Many assume the baby is hungry, but feeding a baby every time he cries isn't a good idea, especially if the baby has a tummy ache. So, it is nice to learn what the different cries sound like and what they mean. This link discusses the various cries:
Alertness & Crying
When a baby's cries all sound the same, it can indicate a variety of problems including communication, neurological, structural (airway, abdominal, etc.) and cognitive delays. But sometimes once we learn to decipher the various cries and what they indicate, we notice the baby does have various cries. Maybe he has one for when he's hungry and another one for when he has pain (tummy ache, fever, etc.), and maybe even another cry for when he's bored. But when this isn't the case, it is definately something to discuss with the child's pediatrician.