Speech Difficulties in Children

Speech is the verbal method of producing language (words and sentences). Speech abilities grow and develop alongside language abilities, and are usually fully developed by 5 years of age. Children with speech difficulties may;

  • be hard to understand, especially to people unfamiliar with their speech.
  • substitute/ simplify certain sounds
  • use the wrong sounds in words
  • be either consistent or inconsistent with their errors.
  • withdraw from speaking situations due to difficulties with being understood

As sounds are usually learned in a developmental order, from easiest to hardest, young children often use sounds that are simplified versions of the ‘target’ sounds – this is to be expected. However, when speech development is delayed, intervention is appropriate. Following is a rough guide of how well a stranger (or person unfamiliar with your child’s speech) should be able to understand what your child says at different ages:

  • Child aged 12 months – about ¼ or 25% intelligible to strangers
  • Child aged 24 months – about ½ or 50% intelligible to strangers
  • Child aged 36 months – about ¾ or 75% intelligible to strangers
  • Child aged 48 months – 4/4 or 100% intelligible to strangers

It is recommended your child’s speech skills be assessed by a qualified speech pathologist if:

  • you, your friends or family are finding it difficult to understand your child’s speech
  • you are concerned that your child’s speech development is behind that of other children the same age
  • your child’s school or pre-school teacher has expressed concerns about the clarity of their speech
  • your child is being teased or having trouble making friends at pre-school because of their speech problems
  • your child gets frustrated because people don’t understand them
  • you have noticed your child withdrawing from, or ‘giving up’ conversations because others can’t understand them

Speech difficulties can fall into a few different categories and each require different therapy approaches.


Articulation refers to movements made by the tongue, lips and jaw to form speech sounds. A common articulatory error is a lisp, where the child may say ‘I thaw Tham thit down” instead of “I saw Sam sit down”. A lisp can be interdental, where the tongue pokes out between the teeth, or it can be lateral, where the air escapes from the sides of the tongue which results in a wet or ‘slushy’ sound. While some young children may grow out of an interdental lisp by around age 4, a lisp that persists past 5 years old is unlikely to correct on its own and will require therapy. A lateral lisp is never typical and will require therapy to correct.


Phonology is the study of how sounds are organised and used in languages. Phonological processes are patterns children use to simplify their speech. Sometimes this has the downside of changing the meaning of their message and making them hard to understand. For example, a child might not yet have developed the ability to produce the sound “k”, so might use the sound “t” instead – but in doing so, they might say “tate” for cake, or “tar” for car. Phonological processes are a natural part of speech development, but when they persist past typical development, intervention is appropriate.

Sarah Masso‘s area of research is with children who have delayed phonological development

Childhood Apraxia of Speech (CAS)

Apraxia of speech is a rare motor speech disorder. Put plainly, it is a disorder that when the brain tries to tell the speech muscles how and where they need to move, the message gets scrambled. This results in difficulties saying speech sounds and with the intonation (or prosody) of speech. Often children with CAS can sound quite monotone or stilted, almost like a stutter, as they struggle to produce their words.

Whilst CAS is a serious speech disorder that will not ‘go away’ without therapy, it should be noted that it is NOT a disorder of the muscles themselves or an intellectual disability.

Dr Patricia McCabe is a world leader in the research and development of treatments for CAS, and is available to provide second opinion assessments for children with suspected CAS.

Speech Difficulties in Adults

After a stroke, 20% of people find they have trouble with their speech. This may be due to a breakdown in the motor speech plan (dyspraxia) or where the muscles themselves have become weak, stiff, or poorly coordinated, affecting a person’s ability to produce clear speech (dysarthria).