My two youngest boys are 17 months apart. Everyone said it would be hard in the beginning but honestly, save for a few things like a serious lack of showering, a huge double stroller to learn to maneuver & occasionally forgetting to brush my teeth, it really hasn’t been all that bad. 
So, What is it really like?
Well…
I was lucky. Little E has always been a fantastic sleeper. My biggest worry when having a new baby was that Mr. C would be completely shafted of my time. In an effort to make sure he wasn’t I tried to capatilize on all that baby sleep to continue to have one on one time with C as usual.
How about getting out of the house?
Sure, you can do this!
Despite having to lug a 20lb toddler in one arm and a 20lb carseat-baby combo in the other for trips between the house & the car, getting out wasn’t so bad. At 17 + months C was still pretty confined to the stroller. Once we were actually loaded into the car and at our destination it was pretty easy because C would just ride. Now that he’s older he wants to walk everywhere and let me just tell you it’s hard to chase down a toddler with a big ol’ double stroller in tow. Or chase down that big ol’ double stroller when said toddler sends it rolling down the aisle at Target (YUP! That happened). Oh and by the way…
Getting out of the house often takes more time than the actual errand itself!
You will begin to rethink every errand or outing in terms of whether it’s worth the amount of time and energy invested to get your toddler and baby dressed, into the car, then into the stroller, and back again. Most of the time you will deduce its not worth it.
(Little E pretty much sums up how I feel about that).
There were a few little things that made life easier…
Like snacks & PBS kids app. Those two things were especially handy to keep C happy if I did happen to be out and had to nurse the baby. And if I was nursing at home books were a lifesaver. C and I would often snuggle up on the couch and read a few good stories while I was nursing E. After a while he might even hop down and play on his own for a bit. Having a 9 year old big brother around the house doesn’t hurt either but 5 out of 7 days a week he’s in school all day!
Some routines needed a little tweaking.
Like grocery shopping for example. I quickly learned that a grocery cart which also contained a toddler and an infant in carseat could not really hold much in the way of actual groceries. I gave it up and started doing food shopping on the weekends when hubby could stay home with the kids. On the rare occasion you do manage to somehow get all the food shopping done with both babies in tow, once you get home and figure out how to get all those grocery bags into the house (along with the babies) you will more than likely not have time to put the groceries away before someone needs to be fed, changed, napped or otherwise melts down from sheer lack of attention. You will forget bags in the car. It will be the fish you were planning on having for dinner (Yes, that happened too).
There were some surprises.
Like how I actually looked forward to middle of the night feedings this time around. It meant quiet time to snuggle one on one with Little E. I was tired but I lived for those extra quiet cuddles in the middle of the night. 
Honestly, being so young C didn’t really care there was a baby was in the house, in fact he pretty much preferred to ignore his new little brother completely in the beginning. He would deny him on any occasion. If asked if that was his baby he would simply say “no”. He rarely got jealous, but he did make it known that my attention was required in between bouts of caring for baby 
Would I do it again?
In a heartbeat. Are you kids close in age? How did (or do) you manage?