I have two kids, one in college and another almost there, so I am still paying. I have not voted, and probably won't because I don't know the answer, and can't really know the answer until I see the situation. It could be any of the above, or most of the above. Here's what I think I'd do, if:
-they're still young, not really been solid on their feet yet, living in apt nearby,
a) invite them to live with us until they got a job. If they had any money, I would collect a token rent, but would give it back when they were ready to move on
-more advanced in years and maturity with a modest mortgage and predominantly LBYM lifestyle, living further away, then b) I would probably visit them to check on their circumstances, ask them if they needed help and if so, ask them to disclose and discuss their finances with me so I could determine how best to help them. In this case, I may be willing to pick up some or all of the mortgage for a few months while they were looking.
-If they had a happy go lucky, devil may care attitude about money, and came asking for support, then c) I would visit them, ask them to disclose their finances as above, but as a condition for any help I would ask them to work out a plan and a budget with me, specifically spelling out what they were going to do (i.e., sell the boat, the timeshare, the motorcycles and the RV) to reduce their debt, the job search plan, and how I could help with immediate needs. In a situation like this, I am very likely to go to the grocery store and buy them a bunch of food (and maybe even a freezer to put it in) rather than to give much in the way of money.
In most cases, I would not let them go hungry or homeless, but I would only give or lend money where responsibility is shown on their part. If they are not able to do that, I will go shopping for them, and their diet will have lots of beans and rice. I'm willing to live on beans and rice to support them that way, if I have to, in addition to giving up vacations. If, after counseling with me, they were not able to give up the extras, I would not offer, or would cease any support currently offered. If they ended up homeless or hungry in this case, it would have been by their choice, not mine.
BTW, when we built our home, we did so with the presumption that it was possible that one or both the kids will either visit or need to move back home with their kids for a period of time...at the same time. We are largely set up for it should it become necessary (but still perish the thought of a long term move back home...thus the collection of a token rent mentioned above).
Slightly off topic, but still relevent:
All of this said, MIL and SisIL seem to be in dire straits right now, monetarily speaking (MIL lives with SisIL). MIL essentially hands her SS money to SisIL when she gets it...SisIL spends it frivolously, and then tells MIL to complain to us that they don't have enough money for food. We lent SisIL $600 last month (again...don't expect to see it returned, along with the other $25-30k lent/given to FIL/MIL and SisIL over the past 8-9 years). DW and I have decided that we will no longer support them with greenbacks, but will buy and deliver enough food for MIL to not go hungry.
This is a sad situation where people who were formerly well-to-do ended up too deep in debt because they could not learn to LBYM, could not change their spending habits when their earning power declined, which eventually pushed them into bankruptcy.
R