Tex. Ins. Code § 823.254

If a domestic insurer's total liabilities, as computed for National Association of Insurance Commissioners annual statement purposes, are less than 10 percent of the insurer's assets, the insurer may invest any amount in the securities of one or more affiliates organized for any lawful purpose if after the investment, treating the investment as if it were a nonadmitted asset, the insurer's policyholders' surplus is reasonable in relation to the insurer's outstanding liabilities and adequate to its financial needs.