Board Thread:General Discussion/@comment-26509198-20160713214402/@comment-25926288-20160713223853

That's because Barbara Hershey is a wonderful actress and she was around for filming in present day so they used her for both. Cost efficient, too.

Cora was likely around her early 20s and Eva around her late teens. If Eva and Leopold have an age gap, then Cora is younger (or similar in age) to Leopold, but older than Eva. Plus, some people just like in life age differently than others.