Salvation Army Refused to return illegal donation ,violation of estate probate, Riverside, California

My older sister donated a precious family antique from my parents "estate" to the Salvation Army in Riverside, CA (she is not responsible for her actions).  My parents had little of anything of value except for a few antiques.  The other 2 heirs were to be notified if ANYTHING was to be given away or sold.  This, of course, did not happen.  I found out about the illegal donation a few days later and attempted to retrieve this item from the Salvation Army.  I got the classic runaround - "call this person"  "no, call this person"...etc, ad nauseum.  I finally got someone who had some authority, was told no can do - we don't even know where it is...then this "Christian" employee of this "Christian" group insulted me!  I am consulting with my probate attorney on this - meanwhile my poor deceased mother is rolling in her grave as some stranger will buy this antique from our family and probably wind up taking it to the Antiques Roadshow to be told what a "steal" they got after they tell them they bought it for $25.00 or so...STEAL - that's what this is.  Forget trying to get ANYTHING back from these blood sucking vampires!  DON'T DONATE MONEY OR ITEMS to these con artists!