James and Sarah are likely close relatives of Robert Robinson. They are the only Robinson family in Lindley in 1841.
1820 to 1831, Edmund, Grace and Sarah were all living at Winter Hill, Longwood when baptised, although Sarah was not their daughter but illegitimate daughter of Mary.
In 1841, James and Sarah (51 & 52) were living at Salendine Nook, Lindley with Sarah (listed first) and then John and Edmund. Grace was not there.
In 1861, there ares George, James, Joseph and Thomas Robinson, all mentioned at Lindley-cum-Quarmby, at four different addresses.