Informing a sick person of a relative's death: Moed Katan 26b
"Recent News"
"Recent News" is defined as that which arrives within 30 days of the death: Eruvin 46a; Moed Katan 20a
Upon receiving news of a recent death, one keeps the 7 Day and 30 Day periods of mourning: Eruvin 46a; Moed Katan 20a
Recent news received on a Holiday, where it will turn into "Distant News" after the holiday: Moed Katan 20b
The Above, where it is Shabbat instead of a Holiday: Moed Katan 20b Tearing Clothing in the above case: Moed Katan 20b
"Distant News"
Upon hearing of a death which happened a while ago, one keeps 1 day of mourning: Eruvin 46a; Pesachim 4a, Moed Katan 20a
Source for keeping 1 day: Moed Katan 20a
Differentiating between distant news about his parents' death and that of other immediate relatives: Moed Katan 20a
Considering part of the day to be like completion of the day: Pesachim 4a, Moed Katan 20b
