Short answer. No. Article 1065 of the Civil Code specifically provides that parents are not obliged to bring to collation any property donated to them by their ascendants when those parents later inherit from those same ascendants. The gifts your parent received from your grandfather stay out of the collation calculation.
What the law says
Parents are not obliged to bring to collation in the inheritance of their ascendants any property which may have been donated by the latter to their children.
Civil Code, Article 1065 — Parents Need Not Collate Gifts to Their Children. Read the full provision →
What collation is and why it normally matters
Collation is the process of accounting for lifetime gifts when dividing an estate — gifts given to heirs during the donor's lifetime are added back to the estate for computation purposes so that each heir's total benefit (gift plus inheritance share) can be compared fairly. Without collation, one heir who received generous gifts could also take a full share of the estate, while another who received nothing took the same share. Collation prevents that distortion by treating lifetime gifts as advances on the inheritance.
The Article 1065 exception for parent-to-child gifts through a grandparent
Article 1065 carves out a specific exception. When a grandparent donates property to the grandparent's children — that is, to the generation below — those gifts do not have to be collated when those children later inherit from that grandparent. The logic is that gifts from grandparents to their children (your parent's generation) were made for purposes the grandparent controlled, and requiring the children to collate them when inheriting would impose an accounting burden that the law does not consider necessary or fair in this particular direction of giving.
What this means in the current estate settlement
When your grandfather's estate is being settled, your parent does not have to declare the gifts received from your grandfather and subtract them from your parent's share. Your parent inherits their full portion of the estate without reduction for those earlier gifts. The other heirs — your parent's siblings, for instance — cannot demand that those gifts be counted against your parent's share. Article 1065 removes the obligation entirely from this direction of the family relationship.
Distinguishing from other collation scenarios
Article 1065 applies specifically to gifts made by an ascendant to their children, when those children later inherit from the same ascendant. It does not affect collation rules in other directions. If a parent (your grandfather) gave gifts to their grandchildren directly, different rules may apply. And if the estate being divided is your parent's estate — not your grandfather's — and gifts were made by your parent to your parent's own children, the ordinary collation rules would govern that analysis. Article 1065 is narrow in scope but decisive in the situation it covers.