Speech difficulties included dysarthria (all HMD genes), language delay (infantile‐onset DDC‐, ATP1A3‐, FOXG1‐, GNAO1‐, PDE10A‐, SLC6A3‐, and TH‐related HMDs), bradylalia (neurotransmitters defects), and dysphonia (KMT2B). Here, SLC6A3 is linked to hereditary mucoepithelial dysplasia.