Help dating 3 tintypes taken in Rochester, NY

[sparrett]

Hi
IMO the children are 3 years old.
There is not 9 months between them and they may not be siblings at all.

Sue

[Neale1961]

I think the boy is older, but the age gap is only a year or less. His arms and legs are noticeably longer, and his face less baby-like.
It is possible that the little girl is the same child as appears in photo 3 standing beside and leaning on her mother.

[IgorStrav]

It is possible that the little girl is the same child as appears in photo 3 standing beside and leaning on her mother.

I wondered that, too, Neale, but the older standing girl has a distinct 'widow's peak' in her hair, which the young child isn't showing?

[Neale1961]

Rather than a widow’s peak, I thought it was a shadow or blemish on the Photo near her hair.

[jim1]

1st. 1860's/70's.
2nd. 1880's.
3rd. 1870's. This may be a mourning photo.
She has black silk tape around her wrists & I think I can detect black crape
on her sleeves.

[IgorStrav]

Rather than a widow’s peak, I thought it was a shadow or blemish on the Photo near her hair.

Oh - maybe......

[tcoyle20]

I had a theory that the three kids were siblings, but based on comments it seems unlikely. I attached a few more photos to help explain. But I guess it's back to the drawing board!

Mother
Johanna, 1834-1912

Kids
William, 1868-1948
Mary, 1865-1944
Frances, 1857-1917

[tcoyle20]

I should have clarified, the tintype of the boy and girl I thought could be brother William and sister Mary. But they would need to be 2 years apart.

The only thing that bothers me about the tintype photo is the difference in the chairs. It seems to create an illusion that they are the same size. The girls chair seems larger, longer and lounged back a bit. I don't know how an old lens might react to that, but perhaps the photography did that on purpose?

But I think I might be biased as well because I want my theory to be true.