under US law, mortgage companies must allow a close relative heir to continue with a mortgage on a house they inherit.
Added (1). According to the Garner-St Germain Depository Institution Regulation act of 1982 prohibits a lender from exercising any due-on-sales clause as long as the property is transferred by will to a surviving spouse, children or close relatives and they move into the house as their primary residence.
(details borrowed from another use, but they are correct)
Read more: In the US, a close relative heir essentially assumes a mortgage as long as they pay, is it different for a 2nd mortgage?
