18th century pair of needlepoint pictures

A fine pair of silk and wool needlepoint pictures worked in polychrome threads. Each depicting a vase of flowers and dated 1730.

One is initialled ‘IB’ the other ‘MB’. The writing on the reverse of each picture is quite faded, but we can make out Isabel and the date 1710 on one, and Margaret on the other with the date 1718 or 1708.

As far as we can decipher the writing on one says ‘Supposed to be Margaret d(aughter) of (Rich or Ed)ward Branthwaite of Carlinghill. Christened June 14 1718 (?) or 1708?’

The other says ‘Supposed to be Isabell d(aughter) of Michael Branthwaite of Carlinghill near Kendal, Cumbria.  Baptised September (crossed through) October  ? 1710’

There was a 17th/18th century Branthwaite or -thwayte family of Carlinghill, Westmorland which was quite distinguished around Kendal, Cumbria.

Were they sisters or cousins, as there fathers seem to have different names?

Presumably the writing was added some time after 1730 by a descendent.