**Paying down the equity line and accounting for the loan in his inheritance can be reasonable—provided it leaves your own finances secure.** You can recognize his family’s needs without putting your retirement or emergency savings at risk.

I’d separate two decisions:

- **Your debt to the bank:** Compare the HELOC rate with what your savings earn after tax. Paying it off may make sense if the borrowing cost is higher and you’ll still have ample accessible savings. Interest-only payments leave the $54,000 principal outstanding; HELOC payments can also rise when the repayment period begins. Check that date and any payoff fees. [CFPB guidance](https://www.consumerfinance.gov/ask-cfpb/what-is-a-home-equity-line-of-credit-heloc-en-107/)
- **His debt to you:** Paying off your HELOC does not, by itself, settle his loan. You could agree on affordable payments to you, defer repayment, or arrange for the unpaid balance to reduce his eventual inheritance.

For the inheritance approach, **have a local estate-planning attorney document it in your will or trust and coordinate it with the loan paperwork.** Specify the outstanding balance, how future repayments reduce it, whether interest continues, and what happens if his inheritance is smaller than the debt. That clarity is particularly helpful if there are other children. An inheritance adjustment won’t replenish your savings during your lifetime, and there may ultimately be less inheritance than expected.

If you’re in the U.S., forgiving the loan or changing it to an interest-free arrangement can have gift-tax reporting or other tax consequences; a tax adviser should review the arrangement. Reporting a gift does not necessarily mean tax is owed. [IRS guidance](https://www.irs.gov/instructions/i709)

If a full payoff would leave you stretched, a partial paydown is a sensible middle course.

**What is the HELOC interest rate, how much accessible savings would remain after a $54,000 payoff, and are you already retired?** Those details would make the recommendation much firmer.