Hello jannergray,
Freereg has the baptisms of siblings of Thomas, including another Thomas, baptised in Gresford 12/08/1804, son of Thomas and Ann Thomas, abode Allington.
There was a William Thomas baptised 16/11/1806, son of Thomas and Ann Thomas, abode The Rosset, occupation labourer.
I haven't looked at all of them but the transcriptions for Gresford are pretty good on that site.
http://www.freereg.org.ukI couldn't find a marriage for Thomas and Ann but there is a marriage as follows:
05/09/1797 George Thomas bachelor, of this parish, to Mary Lloyd, spinster of this parish. Witnesses were: Thomas Thomas and William Thomas. Married by Licence.
Jo