Car ride, kangaroo, tree swing, rock-a-bye, and wave are the unique variations on motions that. Electric swings and baby rockers like the 4moms® MamaRoo® Multi-Motion Baby Swing and the RockaRoo® both use motions and noises that mimic womb-like conditions and soothe and relax your little one. Read more here to see how you can give your arms a break, while still bringing comfort to your baby with the best infant baby swing.