The following record may have nothing to do with Thomas:
Lancashire Archives reference number QSB 1/1833/Jul/pt1/69
Title Recognizance
Date 1 Jul 1833
Description Thomas Forrest, Weaver of Mellor, to appear as Reputed Father of the Illegitimate Child of Betty Preston of Mellor
Sureties: James Forrest of Blackburn, Weaver and William Forrest of Preston, Weaver
JPs and Court Officials: J Addison
Comments: None
The child was almost certainly Ann PRESTON baptized 14 Feb 1830 by Betty PRESTON, spinster. Written in the parents christian names column is "Thomas & Betty" with the "Thomas" crossed out.