Resilient Born

Origin Feat

You gain the following benefits.

Ability Score Increase. Choose one ability in which you lack saving throw proficiency. Increase the chosen ability score by 1, to a maximum of 20.

Saving Throw Proficiency. You gain saving throw proficiency with the chosen ability.

(So it can be taken as a Origin Feat or later, because someone can be born with it or gain it more than once for different abilities)