Amending a will
You can amend your will, or replace it entirely, as often as you want. Only your most recent will is valid, and will be implemented.
A codicil is an addition or change made to your will in a separate document of a testamentary nature. The document containing the codicil must meet the same conditions as a will in order to be valid.
However, the codicil may be in a different form from your initial will. For example, a holograph codicil may amend or change the conditions of a notarial will.
Gift "mortis causa"
Your marriage or civil union contract may contain a testamentary provision called a gift mortis causa, meaning that your surviving spouse will inherit all your property. The clause has the same legal force as a notarial will.
If your contract states that the clause is irrevocable, you must obtain your spouse’s consent in order to change it. This will allow you to make a separate will.
If your contract states that the clause is revocable, you can make a will without your spouse’s consent.