Online resources have a great potential for families of children affected by different kinds of disorders. In fact, acquiring knowledge on a child’s disease is essential for parents and carers so that they may understand and adjust to an initially distressful condition, and also increase their participation in clinical decisions. The present study explores the degree of accuracy, alteration or bias of a corpus of selected web texts appearing in websites dealing with autism, Dravet syndrome, Angelman syndrome and others, which were set up with the aim to provide useful information and support. Special attention is given to the range of expressions used to identify patients and in particular to the use of person-first vs. identity-first language, with a view to assessing their relevance and evaluating whether the person-first language issue is indeed crucial in the process of online dissemination of medical knowledge.