Briefly, Sophia's father James Collins (1821-1870) was born in East Hanney, Berkshire and moved to the Forest of Dean, before he was married, in the 1850's. His father was Jonathan Collins (1770-1853) and his mother was Martha Brakespear (or Breakspear) (1782-1838). Jonathan's father was also named Jonathan (1731-?) and his mother was Elizabeth ?. His grandfather was also Jonathan (1696-?).
Sophia's mother Prudence Harris (1827-1916) was born in Lydbrook. Her parents were Richard Harris (1799-?) and Sophia Roberts (1804-1836). It looks as though Richard was "base born" as they not-so-delicately phrased it in those days, his mother being Hannah Harris. I can't be sure of that though and haven't been able to get any farther back with that branch.
Let me know if you can fill in any blanks.