Yes they def get used to routine with one another. I have 2 boys, they are 6 wks apart in age, they sleep at the same time, eat at the same time, even poop at the same time
EVERYDAY! I have just kept them on the same routine daily and they become accustomed to it. Luckily they are both very easy to care for. I have had them both for close to a year now, they both just turned 1 yr old- just took my first full week vacation- both parents had to end up taking off work during the week because both of the boys were so out of whack not being with me, not being together, and being off their routine with their babysitters! It kinda made me feel good though that they really like being here that much
It may take a few weeks but they will def get used to whatever routine you want them to have! After you get into the swing of things-having 2 infants really isnt that hard, I actually enjoy my little ones the most!