If you were stranded on a deserted island...

I have many of the "baby essentials" taking up space in my house. You know, the swing, bouncer, bed, high chair and entertainer. I also have a HugaMonkey (booya), swaddling blankets, pjs, diapers and a changing table (to name a few). 

What is your very favorite baby item? I mean, if you could only take one thing with you (and your baby) to a deserted island, what would it be?! I am trying to decide on the rules here (before everyone says their food processor to make baby food). So we'll say that the basic necessities are covered like food, water, shelter, diapers and clothing. But you just get to bring one "extra" thing for your little one. What would you choose?

The HugaMonkey wouldn't take up too much room in your carry-on...