Parents' total S.P.E.C.I.A.L must be 122 or higher to have a chance at a rare child.

Parents' total S.P.E.C.I.A.L must be 134 or higher to have a chance at a legendary child.

If random_number is greater than 0.85 the child will be rare If random_number is greater than 0.95 the child will be legendary Max = (male_total_special + female_total_special - 14) / 126 There is a special case to handle 'ghost dads' which always results in normal children who inherit from the mother, though it is not clear whether it's actually used or is just an edge case error handler.

(source1) (source2) (proof)Ĭhild stats appear to be calculated at the time of birth.

Maxed parents' proficiency is always Intelligence. S.P.E.C.I.A.L-boosting gear does not affect this calculation.Ĭhildren have a 50/50 chance of inheriting the 'proficiency' (highest stat) of either parent. Children have a small chance of being born either rare (28 S.P.E.C.I.A.L) or legendary (40 S.P.E.C.I.A.L) if the parents' total S.P.E.C.I.A.L is high enough.

Fallout shelter room special