- Ontario's family law framework gives married spouses (and, in more limited ways, common-law partners) specific statutory tools for dividing property and addressing contributions made…
- Courts typically look for three connected elements: 1.
- In each case, the outcome depends heavily on what was actually said and done at the time — not just what feels fair in hindsight.
Family money rarely comes with paperwork. A sibling lends cash for a down payment. A parent covers years of a struggling child's expenses expecting eventual repayment. An adult child moves home and works the family business unpaid, believing they'll inherit or be compensated later. Then the relationship sours, or someone dies, and there's nothing signed to point to.
Ontario law has a doctrine for exactly this gap: unjust enrichment. It lets a court order compensation where one person has been enriched at another's expense, and there's no good legal reason for them to keep the benefit — even outside a marriage or common-law relationship.
This article explains how unjust enrichment claims work between siblings, parents, and adult children, and how they differ from the property claims available to spouses.
Why This Is Different From a Spousal Property Claim
Ontario's family law framework gives married spouses (and, in more limited ways, common-law partners) specific statutory tools for dividing property and addressing contributions made during the relationship. Those tools generally don't apply between siblings, parents and children, or other relatives — a sibling can't file for "equalization" the way a divorcing spouse can.
That's where the general common-law doctrine of unjust enrichment steps in. It isn't limited to spouses; it applies whenever one person has been enriched at another's expense without a legally justified reason, regardless of the relationship between them.
What You Generally Need to Show
Courts typically look for three connected elements:
- An enrichment. The other person received something of value — money, free labour, property, services — that made them better off.
- A corresponding deprivation. You gave up something of equivalent value to provide that benefit, whether money out of pocket, unpaid work, or foregone opportunities.
- No juristic reason for the enrichment. There's no valid legal basis — like a valid contract, a gift, or a legal obligation — explaining why the recipient should keep the benefit without compensating you.
If a court finds all three, it can order the recipient to pay back the value of what they received, or in some cases recognize an interest in specific property connected to your contribution.
Common Family Scenarios
| Scenario | What's often at issue |
|---|---|
| Sibling-to-sibling loan | Was it a loan, a gift, or an investment? Was repayment ever discussed? |
| Parent covering an adult child's expenses | Was ongoing support meant as a gift, or tied to an expectation of repayment or future benefit? |
| Adult child working unpaid in a family business | Was the work compensated informally (room, board, future inheritance), or genuinely uncompensated? |
| Contributing labour or funds to a relative's property | Did the contribution increase the property's value, and was there ever an understanding about ownership or repayment? |
In each case, the outcome depends heavily on what was actually said and done at the time — not just what feels fair in hindsight.
Building Your Case
Because these disputes usually start with nothing in writing, evidence of intent and conduct becomes critical:
- [ ] Bank records, e-transfers, or cheques showing money changed hands
- [ ] Any texts, emails, or cards referencing repayment, a loan, or expectations
- [ ] Records of unpaid work — hours, dates, and what the work involved
- [ ] Evidence of how the money or labour was used by the recipient
- [ ] Any prior instances where similar amounts were treated as loans versus gifts within the family
- [ ] A clear, honest timeline of events, written down while memories are fresh
What a Court Can Order
If a claim succeeds, the usual remedy is a monetary award reflecting the value of the enrichment. In some property-related cases, a court may instead recognize a proprietary interest in a specific asset — for example, where your contributions directly increased the value of a home the other family member owns. Which remedy applies depends heavily on the facts, and this is an area where the specifics genuinely change the analysis.
The "It Was Just a Gift" Defence
The most common response to a family unjust enrichment claim is that the money or labour was a gift, freely given with no expectation of return. Ontario law generally presumes that transfers between family members can go either way, and the burden of proving your side often falls on you as the person bringing the claim.
This is why documentation — even informal texts — matters so much. A message saying "pay me back when you can" looks very different in court than silence.
Frequently asked questions
Can I sue a sibling or parent for money I lent them years ago?
Possibly, but timing matters. Ontario's general limitation period for starting a civil claim runs from when you discovered, or should have discovered, that repayment wasn't going to happen — not necessarily from the date you handed over the money. As of mid-2026, the general period is two years, though this can vary with the facts, so don't assume a specific deadline without checking.
Does it matter that we're family and there was no contract?
Not fatally. Unjust enrichment exists precisely because family arrangements are rarely formalized. The absence of a contract shifts the analysis to conduct, communications, and context rather than defeating the claim outright.
What if my sibling says it was always meant to be a gift?
Then the dispute becomes a factual one about intent at the time the money or labour was given. Courts weigh the evidence on both sides — including how similar transactions were treated in the family before — rather than assuming either answer.
Is this the same as a claim against an estate?
Not exactly, though the two can overlap. A family member's death can trigger unjust enrichment or related claims against the estate if contributions were made expecting eventual compensation that never came, but estate claims involve their own separate considerations.
This is a litigation question
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