Weaning at a bad time?

Sorry but I didn't see your previous post so am not sure how old your daughter is. When I had DS2, DS1 was 22 months old. I had weaned him previously due to the same concern as you (associating the weaning with DS2) about 2 months before I was due. It was a great success until he noticed DS2 with a paci and repeatedly took it from him. In the end Hubby and I decided it was better to give it back to him until we could wean them both. So, in saying all of that, you could try it and see how she goes, or alternately (if you haven't already done so) we found that limiting it to sleep times or when unwell helped us to wean him. Best of luck with it all.