I would suggest they hold off doing anything else. Ideally you don't want to start the NVC process at all if you're wanting your other child's case to catch up. Once the NVC side of things is done and they've been DQ'ed, they'll be scheduled for an interview and then it becomes more hassle to postpone things. So if they haven't already submitted the DS-260, don't until you have the other case at NVC too.
The good thing is that I-130 processing times have come down now, so your daughter's should be approved in the summer, and Montreal has got rid of their backlog too, so the wait for an interview isn't anywhere near as long as it once was. Fingers crossed they're all with you by Christmas.
For timelines, the most helpful thing to do would be to fill yours in (on your profile). You'll then get info from those with similar timelines too, and it would save people asking questions. As you are a USC petitioning for a child, I'll move your thread as this sub forum is for spousal cases.
Good luck.