Hi Dorothy
Much of my Iffland Yanz tree content came from Australian trees where most of the Ifflands and Yanz's settled.
Johanna and Elizabeth had four children including Clara and Maria EVA. Clara (who married a Ludwig Yanz) had a daughter named Eva Yanz who was my great grandmother. Eva Yanz married a Welshman Owen Price Roberts, and they had three children, one of whom was Gwenda Roberts who eventually settled in Petone, NZ marrying my grandfather Mick Ryan, a plumber.
Maria EVA married a chap called Happ and they became winemakers in Aussie. So Eva had an Auntie called Maria EVA.
I think I may have had her entered as Eva but you have drawn my attention to that and its corrected now.
If you search Ifflands and Yanz on Ancestry.com you will find some family trees on the Family Trees section of the search where you might find more information. They are a big family in general. Hope this helps.
Regards
Dave Ross