Can one get a loan if needed against farm property jointly owned by two sisters?

My Mother & sister jointly own 80 acres of Iowa farmland. My aunt is claiming she cannot get a loan, due to the joint ownership, if needed someday to supplement a long term care plan. She has no health problems, so this is more of an estate planning issue. My Mother is almost 95, lives in CA & disagrees with the no loan statement, is in ill health & almost 15 years older & wants to make no changes until her death due to past arguments over the value of each half of the land.