(יח) וַיֵּ֜לֶךְ בְּדֶ֣רֶךְ ׀ מַלְכֵ֣י יִשְׂרָאֵ֗ל כַּאֲשֶׁ֤ר עָשׂוּ֙ בֵּ֣ית אַחְאָ֔ב כִּ֚י בַּת־אַחְאָ֔ב הָ֥יְתָה לּ֖וֹ לְאִשָּׁ֑ה וַיַּ֥עַשׂ הָרַ֖ע בְּעֵינֵ֥י יהוה׃
(18) He followed the practices of the kings of Israel—whatever the House of Ahab did, for he had married a daughter of Ahab—and he did what was displeasing to GOD.
But the JPS translation also adds a footnote:
Emendation yields “sister”; cf. v. 26.
Everett Fox says:
...A last point, of considerable significance, is the lineage of King Ahazyahu of Judah, who makes his appearance in v.25. His mother, Atalyahu, is the granddaughter of King Omri of Israel. Thus, as Sweeney (2007) notes, every Davidic king from this point forward will also be a descendant of the house of Omri. While this might be diplomatically savvy, from the text’s point of view it is yet another fact pointing toward the inevitable fall of both houses.
and as JPS notes, here in verse 26 we have:
(כו) בֶּן־עֶשְׂרִ֨ים וּשְׁתַּ֤יִם שָׁנָה֙ אֲחַזְיָ֣הוּ בְמׇלְכ֔וֹ וְשָׁנָ֣ה אַחַ֔ת מָלַ֖ךְ בִּירוּשָׁלָ֑͏ִם וְשֵׁ֤ם אִמּוֹ֙ עֲתַלְיָ֔הוּ בַּת־עׇמְרִ֖י מֶ֥לֶךְ יִשְׂרָאֵֽל׃
(26) Ahaziah was twenty-two years old when he became king, and he reigned in Jerusalem one year; his mother’s name was Athaliah daughter of King Omri of Israel.
The reference to Chronicles in the EJ article is only Athaliah's marriage, not her parents.
(א) וַיְהִ֧י לִיהוֹשָׁפָ֛ט עֹ֥שֶׁר וְכָב֖וֹד לָרֹ֑ב וַיִּתְחַתֵּ֖ן לְאַחְאָֽב׃
(1) So Jehoshaphat had wealth and honor in abundance, and he allied himself by marriage to Ahab.