Do married children in their parents' home need to make a separate Eruv Tavshilin if they are staying in their parents' home and their parents are making an Eruv Tavshilin already?
1 Answer
It looks like it depends on whether they're eating their parents' food, or are doing their own cooking (using their own supplies or the parents'). In the first case they don't need a separate eiruv, but in the latter case they would.
(Shulchan Aruch Harav 527:18, citing Yam Shel Shlomo)