Growing Sarracenia in Winter
It is absolutely possible to keep young Sarracenia seedlings inside during the winter months. Their care is practically the same as that of Drosera capensis, itself regarded by most as the easiest carnivorous plant to grow: simply give them bright direct light and wet soil in a room-temperature environment.
Direct Bright Light: You will need to keep your plant under artificial lights to keep them growing and photosynthesizing. There are many small desk-top grow-lights available nowadays. Yescom Brand is a reliable favorite. Keep the plants at most a foot away from the lights. Most colors work, but blue, red, and white LEDs work best in our experience.
Windowsills alone in winter will not let the correct aspects of light through to grow the plant, and winter sun puts them into dormancy anyway! The sole exception to this rule is Sarracenia rosea, which can be kept indoors on a windowsill because it's adapted to somewhat lower light, and it has a weak dormancy requirement.
Distilled or Low-Mineral Water: A tray under the pot with water halfway up the pot can be allowed to nearly dry out, but, like your gas tank, never let it go totally dry. This is really the only routine you'll have to think about.
Just Wait til Spring: Once the risk of frost is past, you can put your Sarracenia outside, after which it should remain an outdoor plant for the rest of its life. It may lose many of its old leaves over the first few days and weeks. New leaves produced outside in its first year and especially after transplantation will be very different. The plant will adjust healthily as long as the conditions for low-mineral water and direct sun are met. New foliage may look different from what you've come to expect under lights, but remember that your seedling still has years of growth and development to go, and that one plant can take on many different colors, shapes, sizes, and seasonal growth habits, in variously optimal and less-optimal conditions, or even varying by year. The pleasure of growing them lies in the ways the numerous species and varieties catch our attention at different seasons, on different years, or even on different days.