22 month gap here.
My first had tongue tie and reflux and only napped on me for 6 months.
If my second was as hard to feed I had realised I may not be able to BF him due to also having a toddler.
Luckily the 2 baby was a dream to feed and also LAY DOWN IN THE MOSES BASKET FOR NAPS. it was unknown territory to me!
I found that when he was born, my first needed me more so he was in his swing a lot, content but with less attention than my first had had at that age.
As he got older, he needed me more but the oldest had grown and was able to do more things herself.
So what I'm saying is, if one of them needs you more at any point don't feel guilty as that will even out as their needs change.
At first I would feed and change the baby first thing and he would have his first nap while the toddler and I had breakfast and that routine helped.
I loved it. They are great friends and entertainment for each other, my second has always adored his sister.
I had a double buggy and on bad days we loaded up and went out. If I walked far enough they both fell asleep eventually!
I remember thinking the hard work would really start when the second started walking! By which point his sis was 3.5 so it was all ok 