A baby's first words are music to a parent's ears. But how can you tell if your child's speech and language development are on track?

While every child learns to speak at his or her own pace, general milestones can serve as a guide to normal speech and language development — and help doctors and other health professionals determine when a child might need extra help.

By the end of three months, your child may:

• Smile when you appear
• Startle upon hearing loud sounds
• Make "cooing" sounds
• Quiet or smile when spoken to
• Seem to recognize your voice
• Cry differently for different needs

By the end of six months, your child may:

• Make gurgling sounds when playing with you or left alone
• Babble repetitive syllables, such as "ba, ba, ba"
• Use his or her voice to express pleasure and displeasure
• Move his or her eyes in the direction of sounds
• Respond to changes in the tone of your voice
• Notice that some toys make sounds
• Pay attention to music

By the end of 12 months, your child may:

• Try to imitate words
• Say a few words, such as "dada," "mama" and "uh-oh"
• Understand simple instructions, such as "Please drink your milk"
• Understand "no"
• Turn and look in the direction of sounds

By the end of 18 months, your child may:

• Point to an object or picture when it's named
• Recognize names of familiar people, objects and body parts
• Follow simple directions accompanied by gestures
• Say as many as eight to 10 words

By the end of 24 months, your child may:

• Ask for common foods by name
• Use simple phrases, such as "more milk"
• Begin to use pronouns, such as "mine"
• Ask one- to two-word questions, such as "Go bye-bye?"
• Follow simple commands without the help of gestures
• Say more words every month
• Speak 50 words and understand more

Talk to your child's doctor if your child hasn't mastered most of the speech and language development milestones for his or her age or you're concerned about any aspect of your child's development. Speech delays occur for many reasons, including hearing loss. Depending on the circumstances, your child's doctor might refer your child to a hearing specialist (audiologist) or a speech and language specialist.

In the meantime, encourage your child's speech and language development. Read to your child. Talk to your child. Sing songs together. Teach your child signs or gestures for common items or phrases. Ask your child questions, and acknowledge your child's responses — even if he or she is hard to understand.