GDF2 and pulmonary arterial hypertension: Rare homozygous GDF2 variants in children have been identified in PAH (Wang et al., 2016 and this study), possible PAH associated with HHT (Gallego et al., 2021), PAVM‐related disease (Hodgson et al., 2021; Liu et al., 2020) and non‐immune hydrops fetalis (NIHF) (Aukema et al., 2020).