Sheena:
Here is what I currently have in my tree:
Gideon Anthony b 1825, d 1870 m to Margaret Potter b 1830 d 1897. I have their children listed as - John "Thomas" Anthony b 1865, John Anthony b 1864, Jane Anthony b 1867 and Janet Anthony b 1868.
I then have their son John "Thomas" (my great grandfather) b 1865 married to Margaret Ann Napier. I am assuming the Gideon you are referring to could be my Grandad's brother. I am showing him as b 1902 but have no further information listed at this time. Do you know the year your dad Gideon was born?