birth. Tex.Fam.Codb Ann. § 13.42 (Vernon Supp.1990). During oral argument, counsel asserted for the first time that failure to interpret section 13.42 of the Texas Family Code as allowing for child support retroactive to the birth of Mallory creates a constitutional issue because of the specter of allowing child support back to the date of birth when a child’s parents were married at the time of the child’s birth, but not allowing child support retroactive to the date of birth when the child’s parents were not married at the time of the child’s birth. As the concurring opinion rightfully notes, no constitutional question was raised in the trial court, and it is not presented to us by a point of error. See Prudential Ins. Co. of Am. v. J.R. Franclen, Inc., 710 S.W.2d 568, 569 (Tex.1986) (<HOLDING>). We also recognize that this argument was not
holding that a ruling of the trial court to which no error has been assigned becomes the law of the case and is not subject to review by the court of appeals holding that absent rare fundamental error appellate court should refrain from deciding cases on legal errors not assigned by parties holding that an appellate court may not review errors that have not been assigned by a party or a point of error holding errors which are argued but not assigned will not be considered by appellate court holding an appellate court cannot reverse a trial courts judgment absent properly assigned error