Issues with Edward Jones!

Wife's dad died recently, and left all 7 kids a sizeable chunk in stocks bonds and annuities in several different firms, equity in real estate and land as well. This is in the Midwest.

Edward Jones will not release the shares until every recipient fills out their paperwork.

The issue is complicated by one of the family members who is on full disability for some health issues and she is afraid if losing her monthly amount the gov gives her. 1200.00.

Is it legal for Edward Jones to hold hostage everyone's shares until they get this figured out through lawyers and courts?