Capital Gains Tax Question

[Derek Scott]

Hi, I have a motivated seller ready to sell his Mom's house in Texas. She hasn't been in the property for 5 years and has been in an assisted living facility. The property has been rented out for that period of time. Will she have to pay a capital gains tax on her property if she sells before passing away(Mom is 89)? Trying to help the seller avoid taking a tax hit, but I also want to purchase the property. This will my primary residence and he mentioned rent-to-own until Mom passes on. Thanks for your thoughts in advance!