Jace also used to think the same way as Camilla before. But over time, Jace realized that it was no one's fault, other than him that his other missing soul fled out of his radar.
He knew well enough that the only way for him to track the other missing soul was through the mother, but for some reason, he did not pay enough attention that time.
So even after the mother's death, he did not get a chance to meet the other party's child.
He only stayed around the place for half a day at most, which he later on regretted. He reckoned that maybe, if only he attended the wake and made sure to see it to its ends, perhaps he met the other missing soul as well.