People whose parent had their German citizenship stripped by the Nazis are eligible to restore their citizenship now under the process described in the first link, but only if they descend from
the parent under the following conditions: fathers can pass citizenship to children born in any year, but mothers can only pass it to children born after 1953.
These circumstances are that the grandparent - child relationship began with a
parent's consent or
under a court order, the grandparent is willing to assume responsibility for the child, and one of the
following conditions exists: