Hi Kate - probably nothing but may be worth mentioning. I have come across a family of SLADES living at Hanslope, Buckinghamshire - farmers. Name Arthur (or Richard) SLADE b.c. 1800, married to Ann (or Catherine) Dawson, b.c.1804. 2 children Edward b.c.1822 (emigrated to Aus 1858?), and George b.c.1824 ) married Marianne Croggon b.c.1824, he died 1890 in Aus. I am associated with researching the SLADE family in the State of Victoria and Tasmania, Australia.
I note your SLADE family is an earlier time period, but who knows, there may be an ancestral link ! Let me know if you tie anything together here.
Best regards,