I’m guessing Florence’s and Bernard’s ages are approaching five and three in this studio portrait with their grandfather John Hammell. That would date the photo in the first half of 1915.

This photo is very similar to the one of the two children with their grandmother Sarah Hammell that looks like it was taken maybe a year earlier. Even the backdrop is the same.
Interestingly, if there was any limbal ring “enhancement” of this photo, it was done with much more subtlety than was done on the earlier photo with their grandmother. Possibly there is a little on the children’s eyes. It doesn’t look like anything was done on Grandpa Hammell’s eyes. It does appear that Bernard’s mouth was darkened, as in the earlier photo.
Fascinating what was considered essential to a good portrait at this time.