im not in your ddc but i had to chime in because my daughters were at the births of their younger siblings!
when i had my second-my daughter was 27 months-we assigned a close friend to stay with us(homebirth) to be with her exclusively, so my husband and i could concentrate on the labor-she got to be right there with us when her sister was born. it was truly awesome. she was never weirded out by any of it, and was truly just excited the whole time. she only got weird after i started nursing the new baby(I tandem nursed for the next 2 and half years) and she needed alone time with me, in which i had to hand the newborn over to the midwife and give my toddler the cuddles she needed to reassure her. that was very hard for me-as i jsut wanted to hold my new baby! but it was crucial for my toddler to do that. it was also a natural birth and i was very loud, but she never freaked out once.
fast forward 4 and half years and im having next baby in a hospital-my two daughters are 7 and 4.5 yrs old and once again we have a adult friend there for them specifically to 'corral' them and they show up just in time to watch me push baby out. they are both super excited and happy and watched everything-crowning, pushing, placenta, the whole deal-never once did they get upset or freaked out-my oldest made a gross face at the bloody placenta, but it was totally fine for them. this birth was very different, as i had an epidural, oxygen mask on, etc-so that worried them a bit to see that, but we reassured them that it was normal and nothing to worry about-they did fine after that.
if you want your kids there i think its important to have someone they like and trust to corral them and take them out of the room if need be. that way everyones needs can be managed, and you can have the joyous experience of having the whole family present-my daughters love that they got to be there everytime a new baby was born and i wouldnt have had it any other way!
Heavily tattooed and Dready Mama to my girls. YES we are STILL NURSING! love to and