Why she'll love it: Whether you build a fort out of cushions or set your kids up with a pre-fab structure, they'll get a kick out of having a place to call their own -- no parents allowed! Why experts love it: "Children at this age are developing their own ability to self-soothe and regulate, and often need a bit of a retreat," says Briggs. Our pick: Resembling an igloo, this tent is as easy to move as it is to take down and offers a calm place for your littl...