delivered the opinion of the court;
On May 13, 1988, a petition was filed in the circuit court of Cham-paign County alleging S.L.S. was a delinquent minor (Ill. Rev. Stat. 1987, ch. 37, par. 805 — 3) because he had committed the offenses of obstructing justice and driving without a valid driver’s license. On May 25, 1988, an adjudicatory hearing was held at which S.L.S. ad*454mitted commission of the charge of obstructing justice. The other charge was then dismissed. The court found S.L.S. to be a delinquent minor. Subsequently, a dispositional hearing was held, and, on June 23, 1988, S.L.S. was committed to the Department of Corrections. S.L.S. has appealed.
On appeal, the sole contention of the minor is that the circuit court lacked jurisdiction to enter the decree of delinquency because his father, Junior Smith, had not been served or notified of the filing of the petition as required by sections 2 — 15 and 2 — 16 of the Juvenile Court Act of 1987 (Ill. Rev. Stat. 1987, ch. 37, pars. 802 — 15, 802— 16). The father’s name and his residence, which was within Cham-paign County, were stated in the petition. He had appeared in court but not until the dispositional hearing. The mother was properly served and appeared at the adjudicatory hearing.
The most significant case in regard to the requirements of service or notice prior to entry of adjudicatory orders is still People v. R.S. (1984), 104 Ill. 2d 1, 470 N.E.2d 297. There, the supreme court upheld an appellate court decision reversing a circuit court judgment finding a minor delinquent and committing him to the Department of Corrections. (In re R.S. (1983), 117 Ill. App. 3d 698, 453 N.E.2d 139.) That minor’s parents were divorced but lived in the same city at the addresses listed in the delinquency petition. The minor had lived with his mother but was in the physical custody of his father at the time of the proceedings. The mother had not been served with summons or given notice of the filing of the petition and, unlike the father here, did not appear at any of the proceedings.
Prior to its decision in R.S., in the case of In re J.W. (1981), 87 Ill. 2d 56, 429 N.E.2d 501, the supreme court held that failure to serve or give notice to a noncustodial parent listed in a petition alleging delinquency did not result in grounds to arrest a judgment of delinquency when the petition set forth that the name and whereabouts of the noncustodial parent were unknown. The court concluded that the attenuated nature of the relationship between this father and his blood son born out of wedlock was such that the father was not a necessary party, and proceeding without him did not deprive either the minor or the father of the due process rights as described in the case of In re Application of Gault (1967), 387 U.S. 1, 18 L. Ed. 2d 527, 87 S. Ct. 1428.
In R.S., the supreme court distinguished the situation there, where service upon the mother could easily have been obtained, from the situation in J.W., where only notice by publication, likely to be futile, could have been given in regard to the father. The R.S. court de*455termined no decision needed to be made as to whether the mother was an indispensable party, because, in any event, the statutory notice requirements had not been complied with. The majority held that the failure to notify the mother deprived the court of subject matter jurisdiction of the proceedings. A three-justice minority concurred in the result but concluded the failure to follow the notice procedure did not deprive the court of subject matter jurisdiction but was merely reversible error.
In the case of In re J.P.J. (1985), 109 Ill. 2d 129, 485 N.E.2d 848, the opinion noted the dispute within the court on the jurisdiction issue discussed in R.S. but did not delve further into the matter. In that case, the court held that, when the whereabouts of a parent are stated in the petition to be unknown, any failure of the petitioner to exercise diligence in locating that parent is waived if not raised in the circuit court. Since R.S. and J.P.J., the supreme court has not spoken on the issues involved here.
The State argues that the holding in J.P.J. negates any complaint by the minor as to the lack of notice to the father here because that issue was not raised in the trial court. We cannot agree. Waiver was applied in J.P.J. under circumstances where the petition set forth that the whereabouts of the parent were unknown. Here, the petition contained a statement as to the residence of the father.
After the supreme court decision in J.W., various courts, including this court, took a somewhat expanded interpretation of the precedent of J.W. in regard to notice to noncustodial parents. We stated: “Unless a minor shows some significant relationship with a noncustodial parent that is affected by the adjudication, he cannot *** later be heard to complain about lack of notice” to the noncustodial parent. (In re S.W.C. (1982), 110 Ill. App. 3d 695, 698-99, 442 N.E.2d 961, 964; see also In re Stokes (1982), 108 Ill. App. 3d 637, 439 N.E.2d 514; In re Vaught (1981), 103 Ill. App. 3d 802, 431 N.E.2d 1231.) The State takes the position here that the unserved father was not a custodial parent of the minor and did not have a close relationship with the minor. Citing the above cases, the State contends the court properly proceeded without service on the father.
Mostly because of hearsay information in the probation officer’s report presented for the dispositional hearing, the record does indicate the father, who was divorced from the mother when the minor was three years old, was not close to the minor and did not have custody of him. However, we do not interpret R.S. to allow a failure to serve a parent whose name and address are known even where the parent has no custody or close relationship with the minor. The R.S. *456opinion gives little indication of the relationship of the minor to the mother, who had not been served. However, the court did say that, regardless of whether she was an indispensable party, statutory notice to her was required because of the availability of her address.
The dispute as to whether failure to serve a parent entitled to service deprives the court of subject matter jurisdiction is not an issue here because, as in R.S., the judgment is being attacked directly and not collaterally. The issue was raised for the first time on appeal. The R.S. opinions in the appellate and supreme courts give no indication whether question of service on the absent parent was ever raised there in the trial court. Yet, even the supreme court minority, who found the failure of service not to be jurisdictional, agreed the failure of notice to the mother was reversible error and deemed the error to be preserved.
In the case of In re J.W. (1981), 87 Ill. 2d 56, 429 N.E.2d 501, contention was also made that the court could not properly proceed because the minor’s custodial mother was not served. However, the mother had actual notice and appeared at the adjudicatory hearing. The supreme court concluded that the rights of the minor were properly protected. Similarly, in the case of In re R.R.S. (1988), 118 Ill. 2d 544 (supervisory order), citing J.W., the supreme court reversed our decision in In re R.R.S. (1987), 160 Ill. App. 3d 548, 514 N.E.2d 192, where we had set aside an adjudication of delinquency where the minor was not served with process before the adjudicatory hearing but had appeared at the adjudicatory hearing and was represented by counsel.
Here, the unserved father did appear, but unlike the mother in J.W. and the minor in R.R.S., the unserved father did not appear at the adjudicatory hearing but later at the dispositional hearing. If the issue in regard to the father was merely one of obtaining personal jurisdiction over him, perhaps his later appearance would satisfy that question. However, according to the majority opinion in R.S., the service upon or appearance of a parent determines subject matter jurisdiction. (R.S., 104 Ill. 2d 1, 470 N.E.2d 297.) If that is so, the circuit court did not have subject matter jurisdiction to enter the adjudicatory order and that jurisdiction could not be obtained subsequently. Even if the issue is only one of error, as contended by the R.S. minority, the lack of service on or process of the father at the adjudicatory hearing would render the adjudicatory order erroneous and subject to attack on the direct appeal. The R.S. court indicated that the primary purpose of affording the parents an opportunity to be present at significant juvenile delinquency proceedings is the aid the parent can *457give to the minor. That aid cannot be supplied by a subsequent appearance.
Accordingly, under the precedent of R.S., we reverse the adjudicatory and dispositional orders in this case and remand the case to the circuit court of Champaign County for further proceedings.
Reversed and remanded.
KNECHT, J., concurs.