Who are the parties on that deed? Who was given the life estate? What are the dates of these documents?

Details always matter.

Example: Dad gifted each child a portion via that deed 10 years ago, but Mom got to live in the house until death.

What you need to investigate with these documents is when ownership is legally transferred. If it was inherited upon death, then sold, that will be different than if the kids owned it for 10 years, already.