When you say they go to bed with a bottle, do you mean they have the bottle in bed with them? If so, both children should be weaned from this as soon as possible. It can be very damaging to the teeth(due to acids and sugars sitting on the teeth too long), and can pose a choking hazard. The two-year-old will likely be the harder of the two to break of the habit. So I would start with the nine-month-old.
Try giving the nine-month-old the final bottle of the night, just before bedtime, while still up. Then just put the baby to bed, and let the fireworks fly. I know that this will make for some unpleasant evenings for a few nights. But it will pass. It would be a bit easier if the pacifier was an option. But, perhaps you can try offering a security object. My son slept with a bunny hand puppet until he was 3 and a half. And I bet he would still if he had not lost it. When bunny got lost, we had about 4-5 nights of difficulty getting him to bed. But, in the end, they WILL sleep.
Now, with the two-year-old, it might be a bit more difficult. Is she drinking from a cup during the day? If so, that's a good start. Only allow a bottle before putting her down for nap and bedtime. After a week of getting this routine down, take away the nap bottle, and replace it with offering a cup of something to drink before going to take a nap. Then, after about another week, take away the bottle all together. It's best to not even make the bottle an option after taking it away from her. This will bring some very big, and likely loud, protests. I wish there were an easier way. But, as stressful as this will be for you, it is about the only way to get through it.