Married with a step child (Louisiana). If the parent dies does the step child get half the community property? If so does the surviving parent(not the step parent) of the minor step child have legal control of that property?

A step child is only entitled to what is bequeathed in their parent's will. If no will, they inherit according to LA's laws of inheritance (which are complex).

I don't believe that community property becomes part of the estate, however, the deceased's share of jointly owned property would.

If the heir is a minor, then a trustee would be appointed. However, the child would first be placed with the other bio parent or blood relatives before the step parent.