Her period comes regularly but the bleeding stops for half a day or a day at the beginning and end
Question

                My wife gets her period regularly, but it starts with a little bleeding, which then stops for half a day or a full day. The same thing happens at the end of her period. When should she stop fasting and praying and when should she resume?.
Praise be to Allah.If a woman 
    sees menstrual blood she must stop praying and fasting, and if the bleeding 
    stops during the period it depends: 
1 – If 
    traces of blood remain, such that if she inserts a piece of cloth or 
    whatever it comes out with traces of blood, then the period is not regarded 
    as having ended, and she should still refrain from praying and fasting, 
    whether that happens at the beginning of the period or at the end. 
2 – If the 
    bleeding stops altogether, such that if she inserts a piece of cloth it 
    comes out clean with no traces of blood, then this is the sign that her 
    period has ended, so she is taahir (pure). She should do ghusl and pray and 
    fast and do all that women who are taahir do. Then if the bleeding resumes 
    she should stop again. 
The ruling 
    that being free of any trace of blood during the time of menses is regarded 
    as tuhr (purity) is the view of the Maalikis and Hanbalis. 
See 
    Mataalib Ooli al-‘Nuha, 1/260. 
In the 
    answer to question no. 37839 
    we have mentioned the view of the scholars of the Standing Committee: 
If the 
    menses stops for one day or one night during the time of menses, then she 
    should do ghusl and pray whatever prayers come when she is taahir, because 
    Ibn ‘Abbaas said: “If she sees blood that is heavy or copious, she should 
    not pray, and if she sees the tuhr for a while, she should do ghusl. End 
    quote. 
Majallat 
    al-Buhooth al-‘Ilmiyyah (12/102) 
And Allaah 
    knows best.