Robert Whittaker and Jane Paterson - a mystery

I found this photograph of my paternal grandmother, Lydia Jane Whittaker earlier this year. She is sat on the front row, dressed in dark colours.

From her positioning, I wonder if the man sat next to her with the dark moustache is her father, Robert Whittaker. If so, it would follow that the woman next to him is Jane Paterson. There does seem to be a resemblance between the two women.