Does prayer become invalid by cutting off the row, such as praying between two pillars or between two children? Is this considered like praying alone behind the row? And does prayer become invalid by the presence of an empty space in the row?

We have explained the ruling on standing between pillars, and that it is disliked unless there is a need, and the ruling on a person praying alone behind the row, and that it is valid according to the majority of scholars. So, if a worshipper stands with a pillar beside him separating him from the row, this does not matter if there is a need, but it is disliked without one. He is not considered as praying alone behind the row. The distance that breaks the row has been defined as three cubits or by custom. If this is the ruling for a pillar, then a child standing between a worshipper and the rest of the row is even more subject to this ruling.