Jean, As you know in 1871 census Catherine Jackson aged 26 was with sister Sarah & family (Magee) at Cronkbourne Braddan. In 1861 census Cath aged 17 is in Cronkbourne village, Braddan & it says pupil for occupation & 'sister'. As it seems to me she is the only one in the house & Edward Magee aged 20 in Braddan is unmarried I don't know if it is still sister to Sarah. In Lawsons 1861 census list there is no Sarah Jackson in Braddan . Does the site /source you use give more info? Thanks K