If one has a daughter and son-in-law in kollel and actually living a kollel life (very minimal expenditures, very simple life), are parents permitted to use maaser money to help them out? Any small commitments of support (ex. pay their car insurance) are already being met. No further monetary commitment was made. If allowed, in what form can this be done. ex. pay for groceries for them with maaser money, pay for a sheitel washing, etc.) or does it have to be actual cash?
You definitely can take that money from maaser. In fact it is almost the most preferred cause that you can give your tzedakah to. First of all, because it is supporting torah learning, which is from the first on the list of preferences, and secondly it is for your close family, which is also at the top of the preference list. You do not have to specifically give them cash. If you pay thier bills, even if they are small, it is still an extremely high form of tzedakah, and even if you don’t have a commitment. It can be done in any way that you want, paying for washing shaitels, groceries, tuition of their children, and of course cash, are all considered tzedakah.
Keep up the good work and may you see much nachas from your children.