An itty bitty kitty on my porch

I saw her for just a few seconds...a little tortie or dark calico. She's maybe 6 weeks old. I could be weeks off of that estimate. She ran off when I tried to open the door. I hope she will come back because of the food I leave. I hope Sylvester, who was also out on the porch, will tell her I'm trustworthy. I want to help her and also prevent a cat population explosion in the neighborhood.