Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
If both of you had intended fasting before the time of Fajr and did not commit any act that violates fasting till the sunset then your fasting is correct. The beginning of the time of Fajr while one is in a state of impurity does not affect one’s fasting since impurity of a person during fasting does not nullify the fasting. It is reported that "The Prophet (Sallallahu Alaihi wa Sallam) was in a state of ritual impurity when after having sex with his wife. Then the time of Fajr entered so, he took a bath and continued his fasting".
Allah knows best.