Wills Act 2007, ss 12, 13
Anyone over 18 years old can be a witness to the making of your will. The person does not have to be personally known to you.
However, a person who is a beneficiary under the will should not act as a witness. If property is left to a witness or to their spouse, civil union partner or de facto partner, none of these people will be allowed to receive that gift, unless:
the will has at least two other witnesses who are not beneficiaries, and who are not the spouse, civil union partner or de facto partner of a beneficiary, or
the gift is the repayment of a debt, or
the other beneficiaries (having legal capacity) agree, or
the High Court is satisfied that the will-maker knew and approved of the gift and made the gift voluntarily.