When dragging symbol of Unknown gender from "Family members not in pedigree" over the symbol with defined gender, preserve the known gender.
- open pedigree and create a simple family mother-father-child
- click on Add family member button -> a symbol of an unknown gender will be created in the "Family members not in pedigree" section
- drag the newly created patient over the father node
- father node will lose its gender ( it should not)