I am in Shloshim for my mother. I have been told that for a parent, Shavuot does not take over Sheloshim and I may still not shave or cut my nails. Elsewhere in this blog, you indicate the opposite. Which is it? Also – if shloshim does get subsumed does that mean I lose my priority to be the Sheliach Ztibur?
Shavout will take over shloshim even for a parent, however there are a few differences. By a parent the child may still not take a haircut or shave until after 30 physical days and people tell him that he needs one. This is not specifically for shavous, but for all Yomim Tovim.
You may however cut your nails, and it may even be done on erev yom tov, (according to the Rema – [the Ashkenazi minhag] it should be done close to yom tov).
Regarding your priority to be the shaliach tzibbur, you will still have your priority
Y:D 399-8, O:CH 548-9, Shut Dvar Moshe brough in Sivrei Sofrim 399-73., Divrei Sofrim chap. 51-67.
Regarding saying kaddish Pri Megadim O:CH 148 M:Z 5 in the name of Eliyahu Rabba, that regarding kaddish the avel still has a din of shoshim, regarding priority.