Articulation delays involve the difficulty some children have with the production of specific sounds in speech (e.g. “w” for “r” or “th” for “s”). See below for the average age children learn to pronounce English consonants correctly.
Speech sound development norms
- “P”, “B”, “M”, “N”, “W”, “D”, “T”, “H”, “K”, “G”, “ING”, “F”, “Y”→ age 2-3
- “L”, “J”, “CH”, “S”, “V”, “SH”, “Z” → age 4
- “R”, “ZH”, “TH” (e.g. those) → age 5
- “TH” (e.g. think) → age 6
Source
Phonological processes are different ways that children simplify speech as they start to talk. Phonological disorders occur when these processes are not eliminated past a certain age (e.g. tar for car, gog for dog, or pinning for spinning, top for stop).