Our posts crossed ... too slow typing ...
I think you've found them, Sam. Interestingly, I cannot find 1142/31 on ancestry even when I browse through St. Martin, Birmingham.
Henrietta and Rosetta were recorded together at 31 Cockspur Street in 1851
Henrietta was recorded with her brother William and niece, Pauline Schletter, in 1881
It makes absolute sense that the family were in Birmingham in 1841, in proximity to Martin Schletter, Helen's future husband. Where was Helen, I wonder?
The name Philip Abraham Phillips has come up many times in searches I have done. It always struck me as very likely that he was Abraham's son, but it's good to get confirmation.