Heterozygous mutations in SOX4 (OMIM #184430) are connected to Coffin–Siris syndrome 10 (intellectual developmental disorder with speech delay and dysmorphic facies, OMIM #618506), those in SOX11 (OMIM #600898) to Coffin–Siris syndrome 9 (intellectual developmental disorder with microcephaly and with or without ocular malformations or hypogonadotropic hypogonadism, OMIM #615866) and the ones in SOX12 (OMIM #601947) to generalized epilepsy, intellectual disability, and childhood emotional behavioral disorders [22,23,24]. This evidence concerns the gene SOX4 and Delayed speech and language development.