Watch/Watson, Harney, Bannon, Muldoon

I am researching the Watch/Watson, Harney, Bannon and Muldoon families of Drum.  The Watch surname changed to Watson starting about 1840.  The reason is unknown but it appears that the entire extended family made the change over about a 20 year period.  John Watch/Watson (born 1834 near Drum, died 1906 Odell, Livingston County, Illinois) was my great grandfather.  His first wife, Kate Killian, married 1860 in McLean County, Illinois, May have been from Drum.  Her estimated year of birth was 1825-1830.  She already had a five year old daughter Mary, surname unknown, when they married.  Mary appears to have been born in Illinois.  It is unknown if Killian is Kate’s maiden or married name.  John’s parents were William and Margaret Harney Watch/Watson.  Both died in the summer of 1855 in Kilmacormack townland.  Margaret’s parents were Mark and Rose Muldoon Harney.  William’s parents were Peter and Catherine Bannon Watch.  All but two of John’s surviving siblings immigrated.  Peter remained in Ireland and appears to have continued farming the family place.  I am looking for their sister Rose who may have moved to Dublin.  She may have married a man named Odell or O’Dell.  Apparently she was mentioned in correspondence regarding the disposition of the family farm in Kilmacormack after Peter’s death pre 1906.  Also I am looking for a Drum connection for Kate Killian.