Charani/Ann - thanks for your thoughts. My original email was already long enough so I had omitted some information. Let me add some of it here in response to your thoughts. The actual birth dates of the other 4 siblings is the same as or close to the date given on the baptismal records, so I would expect that Maria was born on or close to 10 Feb 1846. Her elder sister Ann Maria was actually born in St Giles in 1843 rather than St Clement Danes as recorded on the censuses, hence I wanted to keep that possibility open for Maria in 1846. By 1847 at least the family had settled in St Clements. I have also kept my mind open to Maria being recorded at birth as Mary, Mary Ann and Marianne, to name but 3 - the 2 censuses have her as merely Maria. The BCs of Mary Ann Pearce (Mar 1846 St Giles), Mary Ann Pearce, Jun q 1846, St Geo Han Sq, 1, 36, Maria Eliza Callander, Jun q 1846, St Giles, 1, 83 and Maria Pearse Dec 1846 Clerkenwell are NOT my Maria (other detail on the BCs shows that). There is a family legend that says that the elder sister Ann Maria was actually the daughter of a Duke and the Duchess wife of a different Duke and that the surrogate father and mother were paid an allowance to bring her up. I wondered if John Joseph Pearse and his wife adopted the name Calender/Chalner (from Challoner?) as a result. Though it is striking that the 3rd born child was registered as Pearse in 1847 with no sign of a name such as Chalner (until her baptism in 1853). The only child to carry on using the Chalner name in later life was the 1st born Ann Maria, who used it on her marriage certificate. Hence my wish to find out what the names on Maria's BC were. John Joseph himself is described only as Pearse at his inquest in 1856, as is his wife Ann. Ann records herself and her child only as Pearse on the DC of her daughter in 1859, but uses the name Chalner Pearse on the MC of Ann Maria in 1864. I have asked the Westminster Registry Office if I might view the actual registers for Strand and have been turned down. I work to the principle of Peter Calvert (of that very useful site Lost Cousins), that a person is not missing from birth or census records (unless they were destroyed in a fire), but that we simply cannot find them there (erroneous record, poor transcription etc). Any other suggestions of where to look or of any other search strategy would be most welcome. Regards and thanks Lawrence