TINY KITTEN SWEATERS
Tiny kittens need to be kept very warm. They are essentially ectothermic (don't regulate their own body heat) until about 6 weeks. Mom and the rest of the litter help keep babies warm by dog piling, but orphans need your help.
Nursing babies who are kept contained are easily kept warm with hot water bottles/heating pads and blankets in their boxes, but as soon as they become more independent they are at risk of chilling again. If they refuse to return to their heated boxes to hang out, they might need tiny kitten sweaters--especially in the colder months.
If you have a baby who is at risk of chilling, you can make a tiny kitten sweater out of a tiny baby sock very easily! All you do is cut a hole for the head in the toe of the sock and then add two little holes for the front legs, and voila! A tiny kitten sock sweater! Here's Nesli in his sweater!