In contrast, children in both RASopathy groups were rated as having significantly poorer social skills relative to unaffected siblings [NS vs. siblings: mean difference = − 13.2; 95% CI − 20.1, − 6.3; p < 0.001] [NF1 vs. siblings: mean difference = − 11.8; 95% CI − 18.4, − 5.2; p < 0.001]. Here, NF1 is linked to RASopathy.