Inspite of its designation as a family court, the RTC of Bacolod City remains possessed of authority as a court of general original jurisdiction to pass upon all kinds of cases whether civil, criminal, special proceedings, land registration, guardianship, naturalization, admiralty or insolvency.44 It is settled that RTCs have jurisdiction to resolve the constitutionality of a statute,45 "this authority being embraced in the general definition of the judicial power to determine what are the valid and binding laws by the criterion of their conformity to the fundamental law."46 The Constitution vests the power of judicial review or the power to declare the constitutionality or validity of a law, treaty, international or executive agreement, presidential decree, order, instruction, ordinance, or regulation not only in this Court, but in all RTCs.47 We said in J.M. Tuason and Co., Inc. v. CA48 that, "plainly the Constitution contemplates that the inferior courts should have jurisdiction in cases involving constitutionality of any treaty or law, for it speaks of appellate review of final judgments of inferior courts in cases where such constitutionality happens to be in issue." Section 5, Article VIII of the 1987 Constitution reads in part as follows: SEC. 5. The Supreme Court shall have the following powers: xxx 2. Review, revise, reverse, modify, or affirm on appeal or certiorari, as the law or the Rules of Court may provide, final judgments and orders of lower courts in: a. All cases in which the constitutionality or validity of any treaty, international or executive agreement, law, presidential decree, proclamation, order, instruction, ordinance, or regulation is in question. xxxx Thus, contrary to the posturing of petitioner, the issue of constitutionality of R.A. 9262 could have been raised at the earliest opportunity in his Opposition to the petition for protection order before the RTC of Bacolod City, which had jurisdiction to determine the same, subject to the review of this Court. Section 20 of A.M. No. 04-10-11-SC, the Rule on Violence Against Women and Their Children, lays down a new kind of procedure requiring the respondent to file an opposition to the petition and not an answer.49 Thus: SEC. 20. Opposition to petition. – (a) The respondent may file an opposition to the petition which he himself shall verify. It must be accompanied by the affidavits of witnesses and shall show cause why a temporary or permanent protection order should not be issued. (b) Respondent shall not include in the opposition any counterclaim, cross-claim or third-party complaint, but any cause of action which could be the subject thereof may be litigated in a separate civil action. (Emphasis supplied) We cannot subscribe to the theory espoused by petitioner that, since a counterclaim, cross-claim and third-party complaint are to be excluded from the opposition, the issue of constitutionality cannot likewise be raised therein. A counterclaim is defined as any claim for money or other relief which a defending party may have against an opposing party.50 A cross-claim, on the other hand, is any claim by one party against a co-party arising out of the transaction or occurrence that is the subject matter either of the original action or of a counterclaim therein.51 Finally, a third-party complaint is a claim that a defending party may, with leave of court, file against a person not a party to the action for contribution, indemnity, subrogation or any other relief, in respect of his opponent's claim.52 As