HI Aileen -
I have a 27 month old and a 5 month old and it's amazing how it works out, but it does. I coudln't even really explain to you how it works b/c it changed every few weeks as the baby got older. It really helped me ot have my mother stay with us for the first 3 weeks b/c that gave me time w/ the toddler and keeping her routine was really critical in the overall transition. Now at 5 months old, my husband and I really do a lot of teamwork in getting them down. They ahve roughly the same bedtime. I do my DD's bath while DH stays w/ the baby. Then I get her ready for bedtime (jammies, brusth teeth, sometimes I will have enough time to read her a book, etc..) while DH is bathing the baby. THen we swap - I nurse the baby and DH reads stories to DD and he finishes with her and I finish with the baby. It's a lot of bakc and forth, but it's good b/c we each get a special part of the bedtime routine with each child. When my DH is on travel or home late, it's much harder and someone usually goes to bed later than usual. But my DD is learning to stay in her bedroom while i am putting hte baby down for her nap (they have hte same afternoon nap time too! well, within 15 minutes of each other). ANd she is learning to wait at bedtime too, altho, i haven't had to do this by myself often.
We did have to deal w/ bedtime tantrums w/ DD but I think htat was really a reaction to having the baby. That took a LONG time to work thru, but it did pass...just like everything else does.
So, i hope this is encouraging. We love having the 2 of them now. it was fun w/ my DD and I am more tired now, but amazingly, the family time we have with the 4 of us just fills my heart. Good luck to you and your family!!