Mystery: Who Could Have Been The Children In This Photo?

I was looking through some photos. I came across this one.

 I was wondering. Who were the children in the photo? I've been thinking. 



The man in this photo has been idenified as Frederick A. Lankfard.
He was the son of Robert and Charlotta (Dade) Lankford / Lankfard.

 I don't think my Great Uncle Fred had any children. He may have step children. These children could have been his step grandchildren. Or perhaps some of his siblings' children; nephews, niece or his cousins.

I have another photo that looks like the some background. Fred appears to have on the same shirt. pants and shoes. He was wearing a hat and tie in the other photo. I'll share that photo in another blog.

This is just a thought:
I  don't know why.  I think that they could have been Fred's sister, Isabella Nickerson's children. Fred was born in 1878. Isabella's children were born between 1921 - 1938. Fred appears older in this photo. The photo could have been taken in the mid 1930's. or 1940's.

I can't recall where I go this photo. I could have gotten it from my mother. Or it was found with some photos in my Grandmother's home in 1976.

Hope someone can identify these children.

Thanks for reading,
S. A. Blakley