Pathogenic variants in PTEN (Phosphatase and tensin homolog) underlie the multifaceted PTEN hamartoma tumour syndrome.1–6 Marked by macrocephaly, developmental delay, mucocutaneous lesions and an increased susceptibility to diverse cancers (breast, endometrial, thyroid, renal and colon), PHTS presents a diagnostic challenge due to its variable and age-related manifestations.4,7–11. Here, PTEN is linked to Global developmental delay.