Speech Sound Development: When should my child produce this sound correctly?

One of the many cute things about toddlers is how they produce certain words. Many moms can share stories of adorable ways their children once pronounced a word. My own son, Jude, has a few words that my husband had me promise not to correct:

"teslex" for Tesla
"patteren" for pattern
​"flipball" for football

While I won't go into all of the "speechy" explanations of these substitutions, in each example, articulation wasn't the problem, but many times it is. At stages in a child's development, it is okay/developmentally appropriate to say "twuck" instead of "truck". These age-appropriate errors can be quite charming as well. As children get older, these errors are no longer age-appropriate. What once was considered adorable, now becomes a speech movement that has not developed alongside other developmental milestones. 
The important thing to note is that speech is movement. Just like other motor movements--walking, jumping, running--speech movements are learned patterns. When sounds are produced in error, children have to learn a new motor pattern. Learning a new motor pattern is much easier the earlier we can intervene. 

Listed below are average ages of production of consonant sounds. We hope this is a resource to any parent questioning speech sounds. 

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