"Merida is effectively two types of living beings mixed into one. If you want to get her pregnant, you must make sure both get pregnant. Her and the demonic part of her," Lala approached the bed and waved her hand, "Conveniently, they separated into clearly distinct bodies. Just get them both pregnant and it's solved."
"I guess the problem comes afterward, right?" Arad asked and Lala nodded, "Yes, both would get pregnant so you'll end up with twins, not real twins, but twins nonetheless." She waved her palm over Kino and Merida, "If those two had any disagreement or falling out, they'll miscarry as the balance between them would shatter. Anything as petty as a disagreement over dinner food might lead to a disaster. Make sure they are always in harmony."
"How am I supposed to do that?" Arad asked and Lala shook her head, "How do I know? They are your wives, make sure they get along well."