both kids started sleeping through the night at 8-10 weeks. I took maybe 2 days off of work and she went back at 5.5 weeks, we were absolute zombies as well. I was a grumpy as mother fucker lol. especially on this recent one (3.5 month old or whatever) i just know when they get to a certain age it takes a little more for me to get out of bed and pick them up. it has to be pretty obvious that it wont resolve itself. Our oldest is almost 2 and i can count on 1 hand the number of times ive had to get up with her in the middle of the night since she was 2 months old