(a) Marriage contracts and postnuptial settlements shall be enforced at the instance of all persons in whose favor there are limitations of the estate.
(b) Antenuptial agreements may be enforced by a court of equity at the instance of:
(1) The parties to the marriage; or
(2) The offspring of the marriage and their heirs at any time after the death of a spouse; provided, however, that when enforced at the instance of such offspring and their heirs, the court may enforce in favor of other persons.