Bedtime routines

Just wondering - what is everybody’s bedtime routine with their baby especially with older siblings? My daughter is almost 15 weeks old and I’m finding it sooo difficult to juggle giving her a good calm relaxing bedtime routine when I also have a 5 year old and a 7 year old who are both allergic to their beds! I’m on my own a lot as DH works away a LOT, how does everyone else either as a single mama or one like me who’s partner is hardly ever around do it with older kids?! I find myself dreading every single night time as the older two are a mare which disturbs my baby and unsettles her which makes for a whole night of terrible sleep for us both!