A carriage starts with a singular o many spark-mergins, a third spark will be formed and get attached to one of them. At this time the new spark can be absorbed.
Formation
The newly formed spark is still weak so it has to get the energy from the now carrier. For this a ring is formed around the host spark to help with it.
Orbiting
At this stage the new spark begins to orbit through the ring. It can cause disconfort to the carrier but now the sire can get more involve and also provide spark energy through merges. The new spark will also change, from being only a energy ball to a cloud shape.
Break-in
When the orbiting comes to an end, the spark will break the orbiting ring. The carrier will feel a sharp pain but it wont last much time.
Rise of the sparkling
Not an actually emergence. When everything is done, the new spark will only have to feel a presence from the "outside" to make their appearance. Generally is the sire who they feel and will go to. But it can also be a trusted one of their carrier or just the carrier themselfs.
And now stage one of the carriage is complete. Great to your curious cloud baby and care for them for the next cycles.