Baptism c1800 SCANDRETT - Dilwyn

[illumina]

I have a Sarah Scandrett, born c 1799-1801, who gives Dilwyn as her birthplace on all but one census return. My ggg grandfather (William Scandrett)'s son Charles was living with her and her husband (George Anderson) in 1851 as 'nephew', so I presume her to be William's sister (she also witnessed his marriage). However, while there is a William Scandrett baptised in Dilwyn in 1801 (about right for my William), I've failed to find Sarah.

In short, can anyone find her for me?! I wonder if she was baptised late/as an adult, or was born earlier than she stated.

William died in 1841, so I can't check later censuses for his exact birthplace.