Perekonnaajaloo foorum

I am trying to find out who these 4 siblings are.
They seem to be relatives to us but all I know is that they lived in Tallin / Reval. No names.
I also have another picture of them taken few years later were they are by an old huge oaktree.

https://www.dropbox.com/s/u0ychsc1ijis9j6/Reval ...