Deed of Trust

Question: Washington state Deed of Trust?

My parents built a house in 1997, there were no mortgages and liens on it, as they paid cash for land and the house. Now I found out that last month they granted Deed of Trust to my sister. Does it mean that my sister can do whatever she wants to do with the property (sell etc). Or maybe they took out an equity loan on the house?
Any ideas would be appreciated. It is in the WA state.
Thank you

Answer: a Deed of Trust is somewhat like a mortgage. did your sister loan them money against the house?

"A mortgage and a Deed of Trust are security instruments that pledge to the lender an interest in your real estate to secure payment of a promissory note. A mortgage is the instrument, usually held by the lender, by which the property is pledged to secure the payment of a debt or obligation. A Deed of Trust has similar functions, but is usually held "in trust" by a trustee."

http://www.wsba.org/media/publications/pamphlets/realestate.htm

Hard money rehab in Indiana