criminal prosection during a family court issue discussuion

Hi, so, lets say hypothetically someone lied and it crosses the threshold for 2021 perjury act during a legal separation or divorce, will the circuit courts take action on this or just rubber stamo the existing separation agreement, despite it being obtained thru fraud? Will a judge refer it to the Gardai/DPP? This obviously means the children cannot be properly provisioned for, for example, because one party has lied about, for example again, their means.