Short answer. Yes, potentially. The law lists the fact that the person alleged to have been unduly influenced was suffering from mental weakness as a circumstance to be considered separately from family or other relations — the total absence of a family tie does not rule out undue influence grounded in mental weakness.
What the law says
the fact that the person alleged to have been unduly influenced was suffering from mental weakness, or was ignorant or in financial distress
Civil Code, Article 1337 — Undue Influence. Read the full provision →
What undue influence means at its core
The provision defines undue influence as occurring when a person takes improper advantage of his power over the will of another, depriving the latter of a reasonable freedom of choice. The central question is whether the influenced person's own freedom of choice was genuinely compromised in a real, meaningful way — not merely the specific label attached to the relationship between the two people involved.
Mental weakness is its own listed circumstance
The law names several distinct circumstances courts actually consider, and it lists each of them with the connecting word or between them: the confidential, family, spiritual and other relations between the parties, or the fact that the person alleged to have been unduly influenced was suffering from mental weakness, or was ignorant or in financial distress. Mental weakness stands as its own genuinely independent ground for finding undue influence, not merely a subset folded into family relations.
Why the caretaker not being family does not close the door
Because these circumstances are listed as genuine alternatives rather than a set of requirements that must all be present together at once, the total absence of any family relationship between your parent and the caretaker does not eliminate the mental-weakness basis at all. Early-stage dementia genuinely affecting your parent's capacity to reason and decide clearly is the kind of mental weakness this provision recognizes as relevant here.
What still needs to be established
Naming the correct legal basis is not at all the same thing as actually proving the underlying case. Whether the caretaker actually took improper advantage of that specific mental weakness to deprive your parent of a reasonable freedom of choice when signing away the property is a factual question that depends heavily on the specific circumstances of exactly how the transfer actually came about in practice.
Cases citing this provision
These Supreme Court decisions cite the provision above. We list them so you can read them yourself; the summaries of what each decided are not ours to give.
- Republic of the Philippines vs. Roguza Development Corporation, G.R. No. 199705, April 3, 2019 — read the decision on LawPhil →
- Flordaliza Llanes Grande vs. Philippine Nautical Training College, G.R. No. 213137, March 1, 2017 — read the decision on LawPhil →
- Ruben Loyola, et al. vs. Court of Appeals, et al, G.R. No. 115734, February 23, 2000 — read the decision on LawPhil →