Hi,
To do this, simply use the following technic.
Have two variables, "CurrentChild", and "PreviousChild"
-- use "CurrentChild" that is used within the GetNextChild, this one will represent the current child being iterated,
-- after you've process it, just before looping back to GetNextchild, save CurrentChild in "PreviousChild", and then on the next loop, you'll be able to work with both the current and the previous.
would that work? else can you explain what you want to achieve? cause I can't see why you would need two variables inside this action.
else, you may want to simply maintain an int as a reference to a given child, and then you can use simple math to get to a relative sibling.
Bye,
Jean