Babies' first words are music to parents' ears. But how can you tell if a child's speech and language skills are on track?

Children learn to speak at their own pace. But markers, known as milestones, can be a guide to a child's ability to talk. These milestones help health care providers know when a child might need extra help.

By the end of three months, your child might:

• Smile when you appear.
• Make cooing sounds.
• Quiet or smile when spoken to.
• Seem to know your voice.
• Have different cries for different needs.

By the end of six months, your child might:

• Make gurgling sounds when playing.
• Babble and make a range of sounds.
• Use the voice to show likes and dislikes.
• Move eyes toward sounds.
• Respond to changes in the tone of your voice.
• Notice that some toys make sounds.
• Notice music.

By the end of 12 months, your child might:

• Try copying speech sounds.
• Say a few words, such as "dada," "mama" and "uh-oh."
• Understand simple commands, such as "Come here."
• Know words for common items, such as "shoe."
• Turn and look towards sounds.

By the end of 18 months, your child might:

• Know names of people, objects and body parts.
• Follow simple commands that are given with gestures.
• Say as many as 10 words.

By the end of 24 months, your child might:

• Use simple phrases, such as "more milk."
• Ask one- to two-word questions, such as "Go bye-bye?"
• Follow simple commands and understand simple questions.
• Speak about 50 or more words.
• Speak well enough so that you or another caregiver can understand at least half the time.

Talk to your child's care provider if you're worried that your child has a speech delay. Speech delays occur for many reasons. These include hearing loss and other developmental issues. Your child's care provider might refer your child to a hearing specialist, known as an audiologist, or a specialist in speech and language, known as a speech-language pathologist.

If your child hears or speaks two languages, a bilingual speech-language pathologist can test your child in both languages.

To help your child talk, talk to your child. Talk about what you're doing and where you're going. Sing songs, read stories and count together. Teach your child to copy actions, such as clapping, and to make animal sounds.

Show that you're pleased when your child speaks. Repeat the sounds your child makes. A little "baby talk" is OK. But keep in mind that your child learns to speak by copying you.