Stop feeding your baby at night! You have trained him to wake up and eat...that the middle of the night is dinner and snack time. You are BOTH taking the easy way out - he doesn't want to eat during the day, you don't want to lose out on sleep.
Get him out of your room, if possible. When he wakes up, you are easy access, and that is why he will wake up the baby. Besides, most infants will sleep through noises like that.
Absolutely STOP feeding him juice and water. Juice has very little nutritional value and is high in a sugar called fructose. Fructose, esp. on an empty stomach, can cause a spike in insulin and, thus, a spike in blood sugar. The problem is that the pancreas can overcompensate by producing too much insulin in the blood stream, thus far too rapidly lowering blood sugar. We all know what that means, right?? New hunger WAY too soon! That is why simple sugars do not fill us up for long and leave us with low blood sugar! Plus, too much sugar causes gas!
Do not give him 2 8-oz. bottles at bedtime unless he is an anorexic baby who needs the nutrition. He is probably waking up with gas pains that he is mistaking for hunger pangs, bless his little baby heart.
Get rid of the bottle! He is too old for a bottle anyway. My son's last bottle was at 7-months-old. I introduced a sippy cup of water at 4-months-old. From 7 months on, he either got my boob or a sippy cup of breastmilk. Bottles can cause a lot of dependency, not to mention tooth decay. I shudder to think what will happen to your son's teeth, as I am gathering that you are not sending him back to bed after all these milk and juice bottles after brushing his teeth each time.
Things will get worse before they get better, but you need to pull a Super Nanny and let him tough it out for a week in a loving environment. Consider this: once babies reach about 5-months-old, they are physiologically able to go 8 hours at night without a feeding, so make him wait THAT long, at the minimum. If you are worried that you are not being loving enough without the baby feedings, then you can spend some special quality time playing with him and cuddling him, etc. during the day and at bedtime. Get a bedtime ritual that he can look forward to each night. Here is mine, as an example:
Dinner
Hot tub with daddy (conditions permitting)
Bath/shower with daddy
Diaper/pajamas
Brush teeth
Read 3 books (or more, depending on the time)
Gets on his bed
CD music turned on (Baby Einstein or Baby Genius classical lullabies)
Hugs
Kisses
Eskimo kisses
Butterfly kisses
Sniffies (in his ear)
Pinchies (tickles)
Blow kisses (fast and slow)
Night Night
In short, just say NO to night feedings. If he is hungry, he can wait for breakfast and learn to eat throughout the day. Feed him the diet of a toddler avoiding all simple sugars and juice...give him high protein, whole milk (or try whole Lactaid milk), good fats and complex carbs. Your pediatrician should be able to help you or refer you to a nutritionist.
You cannot be a good mom under these circumstances. I wish you the best. Do the hard work now, and you will be a better mom for it b/c you will be more rested, have more energy and, most importantly, you will set the stage for future limit-setting with your toddler. Trust me when I say...it will only get worse if you let your toddler run the show.
BTW, about me: I have 3 boys - ages almost 2, 11 and 13...so I have been through the toddler stage 3 times! I was also a social worker and parent educator for years before I became a SAHM. I have my degrees in Psychology and Education (Master's), but my kids have been my best educators, by far!