N.D.
Hi, J.,
I think the whole CIO thing is oversold, and in your case you will have a toddler watching mom not respond with comfort to her younger sibling, so I doubt that is a good strategy. One thing you might not have considered, though, is that the baby is hungry--when my daughter was 2 and crying to nurse every two hours, I found the most marvelous book, Ferber's "Solve Your Child's Sleep Problems" (obnoxious title, but a lifesaver for me with both my kids) which showed me hers was not a sleep problem but a feeding one. Once she went to bed with a tummy full of food she liked (I started feeding her cereal at night, introducing new foods at midday when she was less cranky), she slept through soundly! An 8PM bedtime when you guys are only together from 6:30 is not late--but it sounds like the routine is working for you, it's just the suck-and-sleep thing that's not. I also used to sing a lullaby while my daughter nursed before bed, and I could get away with humming it a little to her if she woke up--she associated the song with the comfort of nursing, and that put her back to sleep. Considering I nursed her at night till she was over 3, it also made weaning much easier--we just weaned to a lullaby.
Good luck!