Another way of dealing with too many siblings is “curl back”, that is whereby after a certain point, the remaining siblings are curled back to another row below.
In chart editing mode, click on the sibling that you want to be the first curled back, then click on their “…” button, or right-click on them. From the pop-up menu, select “Curl back 1 row”.
The selected sibling will then be dropped down to the next row, the siblings continued in the original order.
To cancel the curl back, again click on the “…” or right-click on the sibling to get the pop-up menu, then click “Clear curl back”. The siblings should again return to the same row.