It feels like Sia hasn’t just reincarnated or regressed once but multiple times. In her first life—the one shown in the past—she had Rael and Lucy as her children. However, in her second life, she had Raelgo instead. That’s probably why Raelgo is aware that if Sia conceives earlier, her previous children won’t be born again. Raelgo even mentioned wondering if he and Rael could exist at the same time in this timeline.
It seems like the events of the second life repeated the first life, except that Sia and Zester had different child/ren, which is why those memories didn’t take root in Sia. This present timeline might actually be Sia’s third reincarnation or regression, caused once more by Zester sacrificing his life. That could explain why Raelgo felt hurt, he realized that Sia doesn’t have any memories of her second life, where he was her son.
Hopefully, in this third life, Rael and Raelgo will be born as twins. Then, after five years, Sia could conceive Lucy again.
It seems like the events of the second life repeated the first life, except that Sia and Zester had different child/ren, which is why those memories didn’t take root in Sia. This present timeline might actually be Sia’s third reincarnation or regression, caused once more by Zester sacrificing his life. That could explain why Raelgo felt hurt, he realized that Sia doesn’t have any memories of her second life, where he was her son.
Hopefully, in this third life, Rael and Raelgo will be born as twins. Then, after five years, Sia could conceive Lucy again.