^ I think it's a bit narrow-minded to say things like 'If you like your sleep, don't have a family'... every situation is different and what works great for some mums and bubs, doesn't work so well for others.
I'm sure everybody who has, or intends upon having, kids is well aware of the fact that they will lose a LOT of sleep - and that's fine, we're prepared for that, but there are so many circumstances in which an overtired parent can actually do more harm than good for their child.

Sleep deprivation has been repeatedly proven to cause, or exacerbate, physical and mental illness, and in extreme cases can lead to severe mental breakdowns or even death (again, I said 'extreme' cases). I'm not suggesting that we all leave our kids to sob themeslves to sleep every night, but I know that a lot of mothers have health issues, such as PND, which are adversely affected by a severe lack of sleep and happy mums = happy babies, so suggesting that a parent 'just put up with it' doesn't help.

I know that everybody's situation is different, but myself personally, well let's just say that if I don't get a decent night's sleep, DD is the one who suffers the next day because I simply cannot muster the energy to crack a smile, let alone run around in the backyard with her, read her endless storybooks, and interact with her on the level she deserves. I also find that if she wakes during the night, going to her and picking her up only tells her 'it's morning, playtime!!' and she refuses to go back to sleep - meaning I'm then up for hours, trying to keep DD quiet so as not to wake the rest of the household, and I don't catch up on that sleep during the day because I have housework to do. If I leave her to settle herself (which she usually does in less than three minutes), the house is soon quiet and everybody can continue sleeping uninterrupted. And the next day, I'm able to be the mother DD deserves - energetic, fun to be around, and much more patient and tolerant of the inevitable tantrums and mischief.
I do not feel that this in any way impacts on my relationship with DD - it's a trust issue. She knows that if it's important, I am there for her in seconds, but if she's woken up for 'no good reason', she has the coping skills to shrug it off and go back to sleep without my help. I'm not saying my way is any better than your way, but it works for us, whereas it might not work for you and your kids, the way your methods might not work for me and my kids, etc.

I also consider myself very lucky in that I have the support of my parents - if DD is having a bad few days and I'm at my wits' end I know that my parents will gladly take DD for the night and allow me to catch up on sleep and get my head together. Other women may not have that support, and it's not just they who suffer for it - it's their children as well.

Sorry for the long ramble, but yeah... sometimes things just aren't as simple and easy as, 'Suck it up, you big lug'.