Kuba was always a fan of the Jolly Jumper (unlike Robert). I remember I could leave him in it for an hour at a time, and he would just love to bounce (Robert only likes it for a few minutes, and then gets bored and wants to come out). Even now, Kuba loves to see Robert play in the Jolly Jumper. And just a few days ago, he asked to go in it himself! He actually still fit in the small strap, so I let him jump around a bit, until I felt like it might break.