Whose babies are these? Could my Comet goldfish in my lily pond have spawned?

I recently noticed many small baby fishes in my lily pond.  I am not sure if they are baby Koi or baby Comet Goldfishes as they are too small for me to determine the breed. My main Koi pond and lily pond are interconnected via a common filtration system. I did not notice any spawning or eggs in my pond as I have been busy and did not pay a lot of attention to the pond in the last few weeks, except the usual feeding routine.

Many months ago, one of my nephews released 4 comet goldfish into my lily pond. He won them at a fun-fair game stall but did not want to keep them at home. So into the lily pond they went, to join the 2 resident smaller Koi.

I believe this babies could be comet goldfish since they are only seen in the lily pond and not in the Koi pond. However, the adult comets are still relatively small (about 4 inch  or 10cm in length measured from nose to tip of tail). The 4 adult comets are all light pink and single colour (like an albino goldfish) but these babies come in all colours – orange, black, pink, white and combination of these.

Picture of the Comet goldfish with one of the larger babies

Or could these babies be Koi? I will probably be able to tell in a few weeks time when they grow bigger.