DadofTwoGirls,
As GGG has mentioned Rule 14 of the Family Law Rules may cover your circumstance if an order from the court is in effect.
For situations where separation agreements are prevailing, the Family Law Act will apply.
See Part IV of the Family Law Act R.S.O. 1990 c.F3
Section 56
http://www.e-laws.gov.on.ca/DBLaws/Statutes/English/90f03_e.htm#BK60
Provisions that may be set aside or disregarded
Contracts subject to best interests of child
56.(1) In the determination of a matter respecting the education, moral training or custody of or access to a child, the court may disregard any provision of a domestic contract pertaining to the matter where, in the opinion of the court, to do so is in the best interests of the child. R.S.O. 1990, c. F.3, s. 56 (1); 1997, c. 20, s. 10 (1).
Contracts subject to child support guidelines
(1.1) In the determination of a matter respecting the support of a child, the court may disregard any provision of a domestic contract or paternity agreement pertaining to the matter where the provision is unreasonable having regard to the child support guidelines, as well as to any other provision relating to support of the child in the contract or agreement. 1997, c. 20, s. 10 (2).
Setting aside domestic contract
(4) A court may, on application, set aside a domestic contract or a provision in it,
(a) if a party failed to disclose to the other significant assets, or significant debts or other liabilities, existing when the domestic contract was made;
(b) if a party did not understand the nature or consequences of the domestic contract; or
(c) otherwise in accordance with the law of contract. R.S.O. 1990, c. F.3, s. 56 (4).
If full and frank disclosure did not occur between the parties, a provision of aforesaid or the whole separation agreement can be set aside at the courts discretion.
I believe you would have to demonstrate on the balance of probabilities that the other party acted in bad faith in regards in previous disclosed information. Once this threshold is met, the court may at their discretion set aside a provision or the whole separation agreement.
6K is significant, however you have to do a cost analysis on the litigation. Costs can be awarded if successful, but its not absolute guarantee.
When you say " Privacy Act" - do you mean this:
Freedom of Information and Protection of Privacy Act
R.S.O. 1990, CHAPTER F.31
http://www.e-laws.gov.on.ca/DBLaws/Statutes/English/90f31_e.htm
Always keep in mind that if the "Family Law Rules" do not adequately cover a situation, a party may make application to have the "Rules of Civil Procedure" apply. Ultimately it is the discretion of the court whether or not to apply the latter.
http://www.e-laws.gov.on.ca/DBLaws/Regs/English/900194a_e.htm
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