Alexis Jr appears on my ggg-grandparents' gravestone as 'Lelue', & is called their grandson. However, I don't know of a daughter of theirs called Jane, whereas they did have a Phebe, & Jane, dr of Phebe, was baptized nearby in 1817.
Ancestry shows an 1851 London Directory, which has Alexis LeLeu as proprietor of a coffee house in Pentonville, though he doesn't turn up on census searches.
Geoffrey White,
Norton, Sheffield