It is very unfortunate that anxiety and or depression runs in families across generations. If the father or mother suffers anxiety, it introduces anxiety in the child in a different way. Father may exhibit anxiety in a different form or in different areas of life whereas the child may develop and exhibit anxiety in other areas. Then when the child becomes a parent, based on the degree of anxiety/depression experienced in the childhood rears it's child with all the ill effects of anxiety. So the grandchild is even more anxious. In any given generation, the condition can go worse if not treated properly or handled appropriately.
If the other family members are extremely kind, understanding and cooperate well with the affected member, then things would remain in control. If the entire set of family members have an awareness about anxiety and depression and it's effect on life of the affected persons, it would benefit the family.