When and how did you stop? LO is only 5 weeks, but she wont sleep more than a couple hours at a time without it at night. she naps great without it in the daytime though. Curious bc shes about to outgrow the ones we have. Also, does anyone know what the little slit is for in the back of the swaddles? I'm sure it's probably something totally obvious, but I've yet to figure it out!