Oh Kris, i feel ur pain (((hugs))). Mya was around 20months old when Bodhi was born. It was very hard for me. Bodhi wanted to feed all the time but we had issues with him attatching properly,so it always took sooo long to feed him. Poor little Mya would cry for attention & would even kick Bodhi when he was in his rocker & thought i wasnt looking. Bodhi also wouldnt sleep for any longer than 30mins which made things harder.
Im sorry that i cant offer any real advice. All i can say, is that it really does get easier. I think Caros advice with a HAB or something of nature might be a real help & may also help paisley sleep.

Anyway, good luck