The Baby Play Kits and Play Gym complement each other, with very little overlap. Both are stage-based to promote baby's brain development. The Play Gym offers a whole year of play for foundational brain development, while the Baby Play Kits target two-month blocks of development for deeper focus. There are some important concepts (like the use of black and white high-contrast images) that are highlighted in both the Gym and in the first Play Kit in particular, but in different ways (so a rattle, a special first book, etc.). Furthermore, we know that many of our parents like to have Playthings specifically for use with the Play Gym as opposed to a set to put in the diaper bag, take to grandma's house, etc. But we know that every baby plays differently and that needs differ depending on lifestyle