Abstract
Adequate assessment, diagnosis and treatment of phonological disorders require information on normal phonological development. While such data exist for many languages, they often do not exist for minority languages such as Welsh. An added factor is that speakers of such languages are often bilingual so, in the case of Welsh, it is necessary to examine norms in bilingual acquisition of Welsh and English. This article reports such a study and provides benchmarks for use by speech-language therapists in the assessment of phonological disorders in Welsh – English bilingual children. Eighty-three children from south-east Wales took part in the study. They were divided into five 6-month age groups (from 2;6 to 5;0), and into two language dominance groups (Welsh and English). There were 42 male subjects and 41 females. Data were collected via two word-lists and from spontaneous speech. The results present the ages at which the consonant systems of the two languages are acquired, and statistical analysis examines the relationships between the linguistic factors and the non-linguistic variables of age, sex and language dominance. Also important to assessment are the normal patterns of substitution used by children in phonological development for sounds not yet acquired. These are described for the present data, especially important being the substitution patterns used for consonants present in Welsh but not in English.