Whose children are discussed?
Radak, Malbim: They are Yo'ash's. They [and the Masa...] are written in Midrash Sefer Melachim.
Why is it written v'Rav, and we pronounce it Yirev?
Radak: "V'Rav" is a noun, like "v'Rav Shelom Banayich" (Yeshayah 54:13). Here it refers to the great Masa (dire Nevu'ah) that Nevi'im prophesied about him. Yirev means that the Masa increased; it is future tense in place of past.
Malbim: The pronunciation teaches that his sons' names were (a) Yirev ha'Masa Alav, and (b) Yesod Beis ha'Elokim. Midrash Melachim discusses them.
What is the meaning of "vi'Ysod Beis ha'Elokim"?
Malbim #1: He was Mechadesh the Bayis.
Malbim #2: Refer to 24:27:2:2.
Why is it called "Midrash Sefer Melachim"?
Radak (13:22): It was constantly Nidrash (sought) to see the matters of the kings.
