Hi folks.
Thanks for the great responses. Some further information:
29 Artillery Lane, Bishopsgate, Spitalfields, London comes from Marshall’s birth certificate which I purchased from the GRO.
The best match I can find on the GRO for Francis is 1851 D Quarter in SAINT MARY MAGDALEN EN BERMONDSEY SURREY Volume 04 Page 45. Mother’s maiden name is Anderson. Without buying the certificate it seems like a good fit.
It seems likely that Henry died. The GRO has Henry Mitchell died aged 2 years in 1844 S Quarter in Lambeth Volume 04 Page 172. Again, I would need to buy the certificate to know for sure, but it seems the best fit when I look at the choices in a search.
William would have been 16 or 17 when they decided to emigrate to Australia, and I have not found a record of him coming out. He might have decided not to come with the rest of the family or have been apprenticed and not been able to leave.
John married Louise Cooper after Sarah died in 1889.
John and Sarah marrying at St Matthews Bethnal Green by banns 20 March 1836 seems to be a good fit.
The Robert Anderson and Ann Mitchell marriage details and the James Mitchell Frances Marshall marriage details are great.
Thanks for the terrific help, everyone!
Peter