I have a misunderstanding of usage of the tenses in this paragraph:
He didn't know what to make of his younger son. He'd thought they'd been close. He'd made a special effort to spend time with Jack while he was growing up. An unplanned baby. He and Jane had their boy and their girl and were content with that. But Jack showed up eight years after Kate, and neither Tom nor Jane had quite the energy they'd had with the first two. But Tom hadn't wanted to shortchange the little guy, thus the special effort.
F. Paul Wilson - Gateways
1). The narration in the sentence "He and Jane had their boy" and it the following sentences takes place in the earlier period that the one in the first sentence (when Jane is already dead). Why does the author use present simple but not present perfect? Is it correct to suddenly change the current time during narration?
2). "But Tom hadn't wanted..." When exactly he hadn't wanted? When he didn't know what to make of his younger son, when he and Jane had their boy or when they didn't have quite the energy?