Yes, adding cotton or wool pillows to your sofa can help with sound absorption in your living room. Natural materials like plant fibers or wool have been found to construct sustainable sound absorbers that help prevent noise pollution. Layering on cozy textiles and placing pillows near windows or doors can catch much of the sound that comes in. Draping cotton or wool blankets over chairs or using thick blankets or wall tapestries can also add more noise-absorbing material to your space.