Thanks again to mp griffiths,
I have been looking into William Simons/Symonds/Symmonds and Sarah, to try and find confirmation of her maiden name as it is not on the parish records of the children's births.
Everything points to Sarah's maiden name being Taysom/e as mp griffiths suggested.
The free Glos BMD index has Aron Symonds b 1841 as mother's maiden name Taysom, as well as Elizabeth b 1847 & Matilda (who was born in 1844 and died around 2 weeks old).
These are definite children of my William and Sarah, so it seems the link is there.
Just to say a big thanks, once again!
Rachael