I made this bubble suit for Sophie May a couple of weeks ago. It's based on a vintage pattern from the seventies. I've made a few alterations to the back - the original pattern called for a back band, but I didn't like the strain placed on it when Sophie sat down, it constantly looked like the straps were going to split right off. The elastic band at the waist and long crossover straps give her a lot more wriggling room.
The fabric was reclaimed from a big roomy tunic that was destined for the Salvation Army bin. My mother's neighbour left it behind with a heap of other things when she moved back overseas. It's a lovely cotton denim which is light but quite hard-wearing.
It fastens up with long button-on straps, and the elasticated legs make it perfect for sand-pit play, which is currently a favourite thing. Sand in your nappy is a not-so-favourite thing (I'm assuming), and the snug legs keeps that horrible, pesky sand out. Which keeps me, her, and the carpet all very happy.