While Sue (Jena Engstrom) is brushing Jenna's hair, Jenna (Carolyn Jones) asks Sue what day it is. Sue replies "Thursday." Jenna then asks the date. Sue says "March 22nd". Jenna asks if the year is 1866. Sue says the year is 1868.
In reality, March 22, 1868 was a Sunday, not a Thursday. However, March 22, 1866 was a Thursday.