Ds1 was 22 months old when ds2 was born - and then I had almost exactly 2 years between ds2 and ds3.
I found that the step up from no babies to one was much harder and more of a shock than from one to two, or from two to three. I think this was because I learned a lot from having ds1 - the tips and shortcuts that you pick up during the first year or so of having your first baby that let you have a moment to yourself for a wee or a cup of coffee - when you have no2, those shortcuts help you manage the time so you can manage two at once.
Plus you are already skilled in things like nappy changing, dressing the baby, feeding them etc, so you don't have all those skills to learn again. And you are well used to sleep deprivation.
I think I was more relaxed with ds2 than ds1, and even more relaxed with ds3 - it was perfectly expressed, for me, by this
Baby No1 drops their toy/dummy on the floor - you wash it in hot, soapy water, sterilise it and give it back.
Baby No 2 drops their toy/dummy - you wash it and give it back.
Baby No 3 drops the toy/dummy, and you lick it or wipe it down your top and give it back.
All three babies in this scenario are now strapping lads - two at university and one with a degree, a career and even a promotion under his belt.