When Does the Sleep Deprivation Get Better?

We're at 8 weeks with our second kid and I feel like a zombie. Our first born was sleeping through the night by 3 months but this one is all over the place. Feeding every 2-3 hours still, up randomly at night, just no pattern at all. I love my son but I'm genuinely concerned about my ability to function at work. How long until babies actually consolidate their sleep? I remember being tired with the first one but I feel like I blocked out how bad it actually was.