Melbourne General Cemetery is not 7 miles from Richmond, more like 3 to 4 miles....perhaps the figure has been mistranscribed. Certainly took me on a merry chase trying to find another cemetery.

Only two main cemeteries in 'Melbourne' in 1854 - the Old Melbourne Cemetery [under the Queen Victoria Market] and the Melbourne General Cemetery at Carlton.
From my resource...
Interred at the Melbourne General Cemetery, Church of England, Section A, Grave Number blank.
HODGKINS
Sacred to the memory of
Sarah
the beloved wife of Color Sergt. Fredk. HODGKINS
12th Regiment
who departed this life on the 12th Dec, 1854 aged 24 years
Much and justly regretted
also
Mary Ann Eugenie
their daughter
who died 13 Jan 1855,
aged 5 months.
The resource was published in 1989.
Perhaps the deaths were recorded by the 12th Regiment.
Cheers
Cando