“One of the objectives of abuse of process is to protect the integrity of the court’s process by preventing a party from relitigating matters that have already been finally determined. As the Supreme Court of Canada held in Toronto (City) v. C.U.P.E., Local 79, 2023 SCC 63, [2003] 3 SCR 77, at paras. 35-55, the doctrine is related to the common law doctrines of res judicata, issue estoppel and collateral attack, but is more flexible because it is available even where, as in this case, one or more parties to the action were not parties to the underlying action. The doctrine of abuse of process also applies to prevent re-litigation of previously decided facts, namely, whether O.G. was brainwashed by her mother: Winter v Sherman Estate, 2018 ONCA 703, at para. 8.”