Does my child have a lisp?

A Parent’s Simple Guide to Clearer Speech

Written by Kristie Owens

May 2025

Does your child say “thun” instead of “sun”? You’re not alone. Many parents notice their little ones swapping sounds or speaking with a bit of a “slushy” twist. It can be cute at first, but when should you start to be concerned? If you’ve ever wondered whether your child’s lisp is a normal part of development or something that needs a little extra help, you are in the right place. This guide will walk you through what lisps are, when to seek support, and how early intervention can help your child speak more clearly and confidently.

What Is a Lisp?

A lisp is a type of speech sound disorder that makes it difficult for someone to pronounce certain sounds, most commonly the /s/ and /z/ sounds. Instead of sounding crisp and clear, these sounds might come out fuzzy, slushy, or like a “th.” For example, someone might say “thun” instead of “sun.”

Lisps occur when the tongue isn’t in the right spot or the airflow doesn’t move correctly during speech. They are fairly common in young children as they learn to speak, and many grow out of them naturally. However, if the lisp sticks around past a certain age, speech therapy may be needed to help correct it.

While some children continue developing normally and outgrow the lisp, others may carry it into later childhood, or even adulthood, if it is not addressed. This can affect how clearly they communicate, how confident they feel, and how well they perform in school or social settings. This is why early support is so important.

Not All Lisps Are the Same.

There are several types of lisps, based on how the tongue moves and where the air flows when someone speaks. Here is a quick overview:

Interdental Lisp – The tongue pushes out between the front teeth, making /s/ and /z/ sound like “th.”

Nasal Lisp – Air flows through the nose instead of the mouth, making speech sound nasal or muffled. This type is often caused by structural issues, like enlarged adenoids or a cleft palate.

Dentalized Lisp – The tongue presses against the front teeth, distorting the sound.

Lateral Lisp – Air escapes over the sides of the tongue, creating a “slushy” or wet-sounding /s/.

Palatal Lisp – The tongue touches the soft palate (the back part of the roof of the mouth), which alters the sound.

Knowing the type of lisp is key, it helps speech-language pathologists (SLPs) determine the most effective treatment. With the right approach, most people can learn to speak more clearly and confidently.

When to Be Concerned?

Here are some helpful points to keep in mind when considering whether a lisp needs intervention:

Age Expectations:

New guidelines for speech sound acquisition for /s/ and /z/ are between the ages of 4-5 when a child is expected to have these sounds mastered. However, /s/ and /z/ are frequently occurring sounds, so if a lisp or distortion is present in these sounds, it can severely impact speech intelligibility. If the child is stimulable for the sound (meaning they can imitate the sound in isolation), then it is acceptable to target these sounds, even if they are younger than the expected age range. Early practice can prevent the lisp from becoming a deeply ingrained motor habit that’s harder to fix later.

Lingering Lisps:

If a child is over age 5 and still consistently producing /s/ and /z/ with a lisp, the error may become more persistent and challenging to correct.  If a child is over the age of 5 and still producing /s/ and /z/ with a lisp, this production of errors in sounds will become “motoric” in that it will be more difficult to correct later down the road. Targeting earlier is better! Earlier treatment often leads to better outcomes.

Impact on Social or Academic Life:

Lisps can affect how children interact with others. Some children may become self-conscious, develop low self-esteem, or withdraw from social situations. In some cases, lisps can also affect reading, spelling, and writing, especially if sound-letter correspondence is unclear.

While lisps are common among children, they should not be overlooked. Even if a child seems to be developing well in other areas, lisps can impact communication and confidence over time. If you have any concerns, having your child evaluated by a speech-language pathologist (SLP) is always a good idea. Early support can make a big difference in helping your child speak clearly and confidently.

Every voice deserves to be heard and understood. 

Final Thoughts.

References:

American Speech-Language-Hearing Association. (n.d.). Articulation and phonology. ASHA Practice Portal. https://www.asha.org/practice-portal/clinical-topics/articulation-and-phonology/?srsltid=AfmBOopqML19cIho4Pfpu2tqK-xgZRPHcc-DsDOZcCk5Lp5MbH63VPWu&utm_source=chatgpt.com

Rvachew, S., & Nowak, M. (2001). The effect of target-selection strategy on phonological learning. Journal of Speech, Language, and Hearing Research, 44(3), 610–623. https://doi.org/10.1044/1092-4388(2001/050)

McLeod, S., & Daniel, G. (2017). Social, emotional, and academic impact of residual speech errors in school-age children: A survey study. Perspectives of the ASHA Special Interest Groups, 2(SIG 1), 25–37. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5708870/