1871 Douglas, district 9, entry 42, 2 Fells Court
William Cowell, head, married, 50, warehouseman, Douglas
Elizabeth, wife, married, 45, Douglas
William, son, unmarried, 20, saddler, Douglas
Elizabeth, daughter, unmarried, 17, general servant, Douglas
Emily, daughter, unmarried, 9, scholar, Douglas

Princes Street (plural not feminine) was laid out in 1871. There are no entries with that address in the 1871 census (April)