Yes, pillows can be re-stuffed when the filling becomes lumpy, flat, or starts leaking feathers. This is an excellent way to extend the life of your pillows without needing to replace them completely. When re-stuffing, ensure to use quality filling, be it down, feather, or synthetic alternatives. Take the opportunity to inspect and reinforce the seams, patch any holes, and ensure the filling is evenly distributed to prevent future leakage.