What can be done if there are problems with this chain of title and can this be heard in which court?

Deceased mother owned a small oil royalty interest, held as Life Estate (not probated). Ownership dispute, based upon chain of title: 1) Mother, sole owner, deeded half to her son, by tenancy in common deed, valid and recorded; 2) About 18 months later, mother “used” entire oil royalty interest (the entire ownership decimal) to establish Life Estate, using Quitclaim Deed, naming son and daughter as equal Remaindermen. Division Order, issued by purchaser of this oil, i.e., the company that buys this oil and issues monthly checks, allowed entire owner decimal interest to be “used” for establishment of Life Estate, by means of Quitclaim Deed, naming Remaindermen (son and daughter, equally). All parties signed, in agreement, to this “use” of the joint tenancy. Mother was advised it is legal for one tenant-in-common to “use” the entire property; this was not intended as a conveyance of mother’s half of the property. 3) About 10 years later, mother made new Quitclaim Deed, establishing new Life Estate, this time naming only one Remainderman (daughter). Son’s signature was not obtained, on Quitclaim Deed or on Division Order, for this last arrangement.