What is the test for accepting a waiver of parental rights from a juvenile court?

Because the juvenile court did not explain the rights to the mother as required nor did it obtain her personal waiver of these due process rights, we conclude it was error to accept a waiver of these rights based only on counsel's representations. Although the waiver was not obtained according to the rules, we deem this error is harmless beyond a reasonable doubt. (Chapman v. California (1967) 386 U.S. 18, 24, 87 S.Ct. 824, 828, 17 L.Ed.2d 705 [error of constitutional dimension is reviewed under stricter standard].)