Move the children and their clothing to another room immediately and keep the affected bedroom’s door closed. Ventilate the rest of the apartment but avoid using that room’s AC as it could aerosolize and spread the spores. For a small, visible patch, a thorough cleaning with a microfiber cloth and a solution of white vinegar or a dedicated mold cleaner can be effective. However, the critical step is identifying and fixing the moisture source—this is often condensation from an AC supply duct in the wall or a small leak.

Given the symptoms and the location (a child’s bedroom with porous wooden furniture), a professional inspection is strongly advised. They can use moisture meters and thermal cameras to find the hidden source of water that you cannot see, which is the only way to prevent rapid regrowth. Reputable companies will provide a lab analysis to identify the mold species, which confirms the health risk level and guides the appropriate remediation method. This scientific approach is crucial for resolving the problem permanently and ensuring your children’s room is safe.