As a Mum with a small age gap (2.5 years - although I consider that a standard gap!) I can say - it is most definitely bloody hard work. One of my friends is due to have a 2.5 year gap and she asked me how I managed it... I'll be honest, I shrugged and said "Erm... Coffee?" not helpful But my ex had a 90 hour a week job, was less than useless and walked out when baby was 6 weeks old.
However I look back at it as the most favourite part of my adult life. It was absolutely amazing. Two tiny humans. It was just me and them in our own cosy world. Dishwasher needed stacking? So what, I'll go to bed early instead. Need to hoover? Nah, toddler group then lunch somewhere.
I watched a video of my eldest singing Incy Wincy to my youngest in bed at 4am one morning, in her super high pitched voice, doing all the actions, and baby flapping her arms and grinning. Baby was 4 months old then. I sobbed for a good half hour after.
Okay so now I want two close together again 
They sleep in the same bed and are so close. It's such a beautiful relationship to watch.