Short answer. Yes. A person may, by an act during life or through a will, entrust the mere power to make the partition after death to anyone who is not one of the co-heirs — an outside, non-heir person can be given that specific task of carrying out the division.
What the law says
A person may, by an act inter vivos or mortis causa, intrust the mere power to make the partition after his death to any person who is not one of the co-heirs.
Civil Code, Article 1081 — Entrusting the Power to Partition. Read the full provision →
The power can be given to any non-heir
The statute permits your parent to entrust the mere power to make the partition — carrying out the actual division of the estate among the heirs — to someone who is not one of the co-heirs. The key qualification is simply that the designated person must be outside the group of heirs; beyond that, the law does not restrict who this outside party can be.
Two ways this authority can be granted
The article allows this to be done either by an act inter vivos — during the person's lifetime, through some act separate from a will — or mortis causa, meaning through a will that takes effect upon death. Your parent has both routes available for granting this specific power to divide the estate to someone outside the family group of heirs.
Extra safeguards when a minor or ward is among the heirs
This provision, together with the rule immediately preceding it, applies even where a minor or a person subject to guardianship is among the co-heirs. In that situation, the person given the power to partition — called the mandatary — must first make an inventory of the property of the estate, and must do so only after notifying the co-heirs, the creditors, and the legatees or devisees. This extra step exists specifically to protect the interests of heirs who cannot fully look after their own interests.
This is a limited power, not general authority over the estate
The article describes this specifically as the mere power to make the partition — dividing the estate among those already entitled to it — not a broader grant of authority to decide who inherits or how much each heir is entitled to receive. The outsider carrying out the partition is executing a division according to the shares the law and the will already establish, rather than being handed discretion over those underlying entitlements. If a co-heir believes the appointed outsider carried out the division incorrectly or unfairly, that is a separate question about how the partition was actually performed, not about whether your parent had the authority to name a non-heir to do it in the first place.