Pennsylvania Statutes Title 20 Pa.C.S.A. Decedents, Estates and Fiduciaries § 2701. Contracts concerning succession

(a) Establishment of contract.--A contract to die intestate or to make or not to revoke a will or testamentary provision or an obligation dischargeable only at or after death can be established in support of a claim against the estate of a decedent only by:

(b) Joint will or mutual wills.--The execution of a joint will or mutual wills does not create a presumption of a contract not to revoke the will or wills.