The instruction وَفَرِّقُوا بَيْنَهُمْ فِي الْمَضَاجِعِ concerns separating children’s sleeping places. As they grow, privacy, bodily boundaries, personal safety, and suitable rest become increasingly important.
Where space is limited, caregivers should still seek an arrangement that is safe, respectful, and appropriate to the children’s ages and needs. The direction is about protective boundaries, not shaming a child or placing one in an unsafe situation.