Rescued very young stray kitten... need advice.

My 12yo daughter (she is a cat whisperer) rescued a tiny kitten from some neighborhood boys. They did not know or would not tell where they got it from and we were not able to find a mama cat that could adopt the kitten. My daughter took on the responsibility herself. She has rescued and raised many kittens before but not as young as this.

The kitten had blue eyes (indication of being very young, right?) but they seem to have gotten darker by now. We've had her a couple of weeks now and I think she may be 4-5 weeks old? I have no idea... probably a little more than that. She has definitely grown a little bit since we took her in.

Very playful at this point, gets sleepy a lot, my daughter fed her baby food (Cerelac) for a while along with meat that we feed our other rescued adult cats and the kitten seems to be doing fine.

My question is... should we be doing more? The kitten will try to suckle on our clothes and even suckled on my daughter's ear. I'm worried that it might need milk still or at least more calcium... we are in a small town in a developing country where there is barely anything we can buy for pets much less anything for cats. The only thing available would be something made for human babies. Should I give her baby vitamins? A vet had us give our dogs vitamins when they were puppies. And I know cats are lactose intolerant but what about powdered milk meant for infants? Can/should we give her this?

She seems fine, healthy, can climb and jump from shockingly high places(such as the couch), but I am worried that her bones might not develop well. What more can we do to make sure she is healthy?