Legal Question in Family Law in Missouri

It is unclear what you mean by "banking papers" If you are asking whehter a step parent can open a cusodial bank accoutn with and for their sterp child, the answer in mosts cases is "yes" Peopele open such accounts for thier grandchildren, nephews.neices or Godchildren.

If you mean can the step parent sign some form, that gives away some legal right of a child to funds held or transferred for the child's benefit, by pretending to be a legal guardian, then the answer in most cases is "no."

Good luck