Witness to marriage - Unna Ann Curtis

One of the witnesses to their marriage was Unna Ann Curtis, the other being John Curtis.
This Una Ann also appears in the 1881 and 1891 Census.  Born at Crowland, Lincoln.
1881 - a lodger with Thomas and Eliza Darby at 30 Hope Street, West Bromwich who apparently had 'income from property' and was born at 'Crowland Lincoln'  She was aged 58, therefore born c1823.
1891 - with Alfred Cox and Una Ann Cadby - aged 72 and given as Aunt.
She was presumably Mary's sister.