Heres a Picture of Ella with her siblings. (I like her costume, is she to be her great-grandmother Sophie?) Hedwig (i think), the girl in the bonnet, she looks exactly like her mother! wow. I can't identified the other children.
I'll try to identify them. From right: Ella, Matylda, Clemens, Franz Karl, Gertrude, Hubert, Marie and Theodor.
I suppose that this photo was taken around 1908, therefore the girl between Franz Karl and Hubert can't be Hedwig.
She was in that time 12, but that girl looks younger. It could be rather Gertrude, who was only one year older than Marie.