To Ferb or Not to Ferb

At one time we were the lucky parents whose little angel slept her first solid 8-hour night at six weeks old, and started consistently sleeping 8 or 9 hours per night by the time she was two months old.  However, around the time that Avery turned eight months old, she started waking up at random times in the middle of the night. Given that she still has no teeth, we naturally assumed that she must be teething, so we would rush in to comfort her and offer her a bottle at the first sound of a whimper. In doing so, we unknowingly created a monster.  It wasn't long before she got used to this routine, and has now been expecting a meal every night between midnight and 3 a.m., and sometimes twice per night.
I discussed this problem with Avery's doctor (Dr. Messinger) on Wednesday. He suggested that we let her cry it out (CIO).  I asked him how long I should let her cry, and he said, "Until she falls back asleep.  Of course it's up to you, but that's what I did with my kids."  Josh and I have discussed this before, so we talked it over again.  This method of sleep training is controversial, and many of the books I have read offer conflicting advice on the Ferber method, although most parents who have tried this have told me that it works like a charm.  The Ferber method suggests going to the baby's rescue after increasingly longer intervals (for example, let them cry 5 minutes the first night, 10 minutes the next night, and so on). But Dr. Messinger and others I have talked with recommend just doing it all at once; don't go in the room at all and eventually she will get the message and put herself back to sleep.  She is old enough now that she doesn't need the calories of a nighttime meal, especially since she was sleeping through the night for months before she started this new routine). Josh and I were concerned that it would be too painful for us to listen to her cry, especially if it went on for an hour or more. We wanted to try other things first, including giving her water in place of formula, since my other concern was that once she does get some teeth, giving her formula in the night can contribute to tooth decay.
At about 2:30 a.m. Wednesday night, we heard the familiar wail, so I dragged myself out of bed and prepared a bottle of water for her, went into her room, laid her back down and gave her the bottle.  But Avery is no dummy, she does not fall for tricks easily!  I had been out of the room for about 0.5 seconds when she figured out that she did NOT want water, cast the bottle aside, and started wailing again. I was too tired to fight with her or stay up listening to her protest, so I caved in, gave her the formula and went back to bed. 
The next morning (yesterday) Josh and I decided that we had to do something. I asked him how long he thought he could stand to listen to her cry. He said he wasn't sure, but I told him I wouldn't last long, especially when I hear her calling "Mamamamamama."  Heartbreaking!  So we figured we would let these shenanigans go on for one more night, and then start the tough love program on the weekend when we didn't have to get up for work.
Last night I filled her little belly with baby food, rice cereal, puffs, and 6 ounces of Formula before bedtime.  This megafeast carried her through until 3:17 a.m.  When the crying started up, Josh and I both woke up but neither of us got out of bed.  We looked at each other and debated whether or not we would cave in one more night, or just tough it out for a little bit and see how long she would cry. I had a feeling that if she cried long enough, she might settle for a bottle of water over no bottle at all.  With this in mind, I had placed a bottle of water in her crib before bedtime, in the corner closest to the door (she always crawls to that corner of the crib and pulls herself up because she anticipates that we are going to come through the door).  So I told Josh we should at least wait and see if she finds the bottle after a few minutes of crying.  After several minutes we turned on the monitor and discovered that she was already in standing position with the bottle at her feet. It appeared that she had quickly found (and rejected) the bottle of water.  But now that we had let it go on this long, I knew that going in and rescuing her was not going to do any of us any good.  She would just learn that crying louder brings one of us into the room.  
I anticipated Ferberization to be excruciating for all of us, but I surprised myself at how callous I can be at 3 in the morning!  I expected I would be in tears, but instead I was digging in my nightstand for my earplugs so I could get some shuteye. And as it turns out, all the stress was for nothing.  Miss Avery only lasted for 13 minutes before she decided that it was just too exhausting to carry on with her fussing, and decided that settling for a bottle of water maybe wasn't so bad after all!  She laid herself back down, and we all went back to sleep.  Josh and I expect that we will at least have three more nights of this until she realizes that there is no point in waking up in the night anymore. 

Avery on the baby monitor at 6:00 am this morning, passed out next to her bottle of water: