Children should normally be listed in birth order (left to right). However, rearranging them on a particular chart can sometimes produce a better visual layout — especially when some children have descendants that cause extra width or blank space.
To change the order: select the family, go to the Family tab of the Chart Properties panel, and click the … button next to Order of children. Use the arrows in the dialog to rearrange them.
When siblings are drawn out of sequence, small numbers appear next to their names on the chart to indicate their actual birth order.
Note — This only affects the chart display; the database birth order is unchanged.