Does the impurity of urine that got on a child's clothes, then was placed on the floor, and a wet mop wiped those clothes and the floor, then the rest of the room was wiped with the same mop, then the place was wiped four times with the mop being washed and squeezed each time, disappear, whether it is certain that the urine reached the floor or not?

If there is doubt about the ground being contaminated with urine, the original state is its purity, and it is not necessary to purify it. However, if one is certain of its contamination, it is purified by pouring water over the spot of impurity until it covers it. If the connected ground has dried, it becomes pure by this method according to many scholars, such as the Hanafis and the chosen opinion of Sheikh al-Islam Ibn Taymiyyah.