C. F. Keil and Franz Delitzsch on 1 Kings 1:6

1Ki 1:6 “And (= for) his father had never troubled him in his life (מיּמיו, a diebus ejus, i.e., his whole life long), saying, “Why hast thou done this?” Such weak oversight on the part of his father encouraged him to make the present attempt. Moreover, he “was very beautiful,” like Absalom (see at 2Sa 14:25), and born after Absalom, so that after his death he appeared to have the nearest claim to the throne. The subject to ילדה is left indefinite, because it is implied in the idea of the verb itself: “she bare,” i.e., his mother, as in Num 26:59 (vid., Ewald, §294, b.). There was no reason for mentioning the mother expressly by name, as there was nothing depending upon the name here, and it had already been given in Num 26:5.