Moreover, a 2-yr-old child with AR IRF9 deficiency (Hernandez et al., 2018); three children with autosomal dominant TLR3 deficiency (Lim et al., 2019), aged 5 wk and 5 and 9 yr; three children with AR STAT1 deficiency, including two aged 1 mo and one aged 6 mo (Le Voyer et al., 2021); and a 10-mo-old child with AR STAT2 deficiency (Freij et al., 2020) have all been reported to have suffered from life-threatening influenza pneumonia. Here, IRF9 is linked to hyperinsulinemic hypoglycemia, familial, 4.