@Candy Kimbro Congrats on your STR property, nice cash flow for sure. Some banks may lend as a HELOC on the rental property, or refinance it. Would have to have all owners on board for this.
I've definitely seen parents purchase properties close to campus to house their kids while they're at school, it's a solid move. My wife and I have a few homes near campus we use as student rentals and they certainly perform well. Averaging $1k/mo per bedroom which is now on the cheaper side of things.
I'd consider doing some kind of cash out refi on the property at a number you're both comfortable pulling out, while still leaving $ for reserves to maintain the STR you currently have. It'll restrict that cash flow, but unlock a nice option for the family. Especially if the other kids follow suit, they'll likely need some kind of housing for a significant period of time nearby so buying now wouldn't be the worst move.
Just my 2 cents. Happy to help however I can