What is the ruling on the Farewell (Ifadah) Tawaf and Hajj for a woman who suspected drops of urine descending during the sixth round of Tawaf, then completed her Tawaf and Sa'i, and then repeated only two rounds of Tawaf?

The majority of jurists stipulate purity from both minor and major ritual impurity (hadath) and physical impurity (khabath), as well as covering the 'awrah, as conditions for the validity of circumambulation (Tawaf). Therefore, whoever performs Tawaf without purity, their Tawaf is invalid. However, doubt about ritual impurity after having achieved purity does not invalidate the Tawaf, based on the Prophet's (peace be upon him) saying: "He should not leave (his prayer) or go away until he hears a sound or perceives a smell." This is also because "certainty is not removed by doubt." Accordingly, your mother's Tawaf is valid as long as she is not certain of ritual impurity.