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, FOXG1 is linked to Onset.