Sec. 4. In determining whether any waiver of rights during custodial interrogation was made knowingly and voluntarily, the juvenile court shall consider all the circumstances of the waiver, including the following:
(1) The child's physical, mental, and emotional maturity.
(2) Whether the child or the child's parent, guardian, custodian, or attorney understood the consequences of the child's statements.
(3) Whether the child and the child's parent, guardian, or custodian had been informed of the delinquent act with which the child was charged or of which the child was suspected.
(4) The length of time the child was held in custody before consulting with the child's parent, guardian, or custodian.
(5) Whether there was any coercion, force, or inducement.
(6) Whether the child and the child's parent, guardian, or custodian had been advised of the child's right to remain silent and to the appointment of counsel.