Have you considered hiring your children to work on your rental properties? This is a great way to take some of that “Parental Welfare” you are paying anyway and deduct it! The compensation must be reasonable and they must be performing real work.
If you own more than one rental property, your children may work on more than one. No problem. You need to allocate the wages and associated expenses to the properties on a reasonable basis, the most apparent allocation basis for the money you are paying the children being time spent by the children at each property. Do this instead of classing it as overhead!
Remember, under the new law, there are no dependents. You kids are considered “single” and receive the same $12,000 standard deduction that every other single person gets. So if the wages you pay are $12,000 or less, they will not pay income taxes and you get a legitimate write-off!