9.5 month old waking early and disturbing 3.5 year old, what do we do?

[MsHB1981]

I'm relatively new to Mumsnet so I'm sorry if this is a bit samey but can't find a thread with siblings involved.

We have 2 girls, 3.5 yrs and 9.5 months, DD1 is a good sleeper put her to bed and you don't hear from her til the morning unless sick or frightened. DD2 was a fairly good sleeper but the last few weeks has been waking early hours and won't go back off and gets to the point she is so loud we worry about DD1 not getting a good sleep. They share a room and we end up bringing DD2 into our room and she sleeps on either me or DH til the morning wake up around 6/7 am, which I know is not ideal but we don't know what else to do, DD1 is very active throughout the day and hasn't napped in the day since she was about 18 months [her choice] so by the end of the day she is ready for sleep, and this morning when I picked DD2 up to bring her to our room I could hear DD1 was awake so I just gently said "it's ok just go back to sleep" and she went off again until 7am this morning.

Some details about DD2 routine, if it helps:

Wake up [in our bed] - 6.30/7am
7.15am ish - Bottle 6 oz
8.15am ish - Breakfast
9-9.30am - nap and she will have anything from 45 mins - 1.5 hours
10.30am [only if awake] - Bottle 3oz
12noon - Lunch
1.30pm ish - naps between 30 mins and an hour
2.30pm - Bottle 5oz
5pm - Dinner
6pm - Bath and Bedtime routine - Bottle 8oz
7pm - Normally asleep by now

Between feeds/sleeps she plays on her mat with toys or with myself/DD2 or visitors.

Other info: She was 6.5 weeks early, she has started rolling over and sits unaided but cannot crawl yet. Last time we weighed her [about a month ago] she was 18lb.

Sorry for the information overload but we would really like some advice from anyone who thinks they could help.

Thanks in advance.

Hello. Your routine is virtually identical to my nearly 10 month old DS, he's been early waking now for about 3 wks most days. Its killing me. We cosleep (dont want to just he's never been healthy enough recently to get him in his own cot) and he still wakes. I'm getting round it now by bfeeding him or getting up and getting a bottle, even though I dont think he's hungry it sometimes gets him back to sleep. So unfortunately no advice just a hello and to say you're not alone :)

Thanks SwivelHips! It's helps to remember we're not alone, but when its 3am and you're being woken up again, it's hard to believe isn't it?
I don't think DD2 is waking through hunger either and no doubt teething is part of it but I'm prepared to take any advice right now.
DD2 has never been into the dummy - which is something else I have tried, DD1 was addicted to it and was so easy to pop it back in and she'd be off [she doesn't have one anymore so that's why I tried with DD2] but there is no option with DD2 there is no way of settling her back off without picking her up and it's got into a habit for her and us which we are finding hard to break, so if there is anyone out there with some words of wisdom I beg you please tell me :0)