I have researched this on and off for about a year. Nothing would make me happier than to be able to verify her existance as I am descended from the Nicholas Stillwell who is allegedly her son. The Hopton line is a fantastic line and anyone would be proud to descend from them. However, I have researched the Peerage records (many times) and there is no mention of Abigail Hopton being a daughter of the Robert Hopton she is supposed to be a daughter of. Each of his daughters is carefully listed in the Peerage records, including each of their marriages, their married names and their children. Catherine, Rachel and Margaret are the daughters of Robert Hopton and Jane Keymesh. Another daughter Mary, is listed as the daughter of Robert, however Jane is not listed as her mother. As for the story of Abigail being a lady-in-waiting to the Queen of Bohemia, Abigail was allegedly born in 1610-1615, the queen of Bohemia married in 1613 and moved to Heidelberg with her new husband. If you do the math Abigail was only a child at that time,(if she existed).
There may have been an Abigail Hopton but I cannot find any valid proof that she was ever in this family. If anyone can come up with documented proof I would be most grateful, as this would allow me to proceed on the correct lineage.