ler, neither being under any compulsion to buy or sell and both having reasonable knowledge of relevant facts.' "' EFTA_R1_02210774 EFTA02724151 Anthony v. United States. 520 F.3d 374.377 (5d1 Cir. 2008) (citing Treas. Reg. §20.2031.1(b)). B. Background Over the course of their marriage, the Texas-domiciled Decedent