Florida law bestows certain rights upon a person immediately upon marriage, including rights to either an intestate spousal share of an estate, or elective share (if the decedent has a Will); homestead rights; the right to preference to serve as a Personal Representative, and rights to certain exempt property.  In estate planning, very often a couple, or one of them, will have children from another relationship for whom the person wishes to give more assets that Florida Law would otherwise permit.  This can be accomplished by a prenuptial or postnuptial agreement.