Thomas Richardson

[Almond Tree]

My ancestor Thomas Richardson was baptised on 21st December 1801 in Derby, the son of William and Sarah Richardson.  I believe there is some connection with Maria Richardson because of her name as witness of family marriage records but I cannot find any trace of her.  Thomas married Dorothy Fox on 21st July 1822 at St Michael Derby.  William and Sarah also baptised Harriet on 29th September 1804 but again I can find no trace of her following her baptism.  I also think a brother William may have married Sarah Kinsey on 27th April 1812 but have no evidence for this other than circumstantial.
I believe William and Sarah were in Ashbourne at one point because Millicent, was baptised there on 20th November 1794 and was buried in Derby on 16th January 1808.  I have been unable to find records for either William or Sarah's deaths.
Has anyone come across these names in their family history research?