(decedent, long-time chairman and CEO of Delta & Pine Land Seed Co. retained possession and enjoyment of stock he transferred to two FLPs and did not transfer the stock in a bona fide sale for adequate and full consideration with the result that the value of the stock was included in the decedent's estate; decedent also made indirect gifts to his children of interests in various LLCs upon transfer to trusts of limited partnership interests in an FLP and transferred to the FLP interests in the LLCs; decedent also made various direct and indirect gifts to his children in the last three years of his life; various deductions for the estate disallowed pursuant to I.R.C. Sec. 2053(c)(2) and other deductions may not exceed the value of estate property subject to claims).