8 month old taking an hour getting to sleep.Struggling with older aibling

[Lyratrain]

Hello
my 8 month old used to be a great sleeper and we would be able to put her in her cot and walk away and she would fall asleep by herself quite happy. It started getting more difficult during the 6 month sleep regression and now at 8 months getting her to sleep takes around an hour. We are trying to not put her in the cot asleep and do it when she is drowsy. But she has to be on the edge of sleep for this to work and she will only get to that point by sucking her thumb whilst being held.
we have tried dummies and comforters and white noise but she won’t use any of them. If she was my first I would just roll with it. But it’s getting really difficult as I can’t leave my 3 year old unattended for an hour whilst I do this (my husband works away a couple nights a week). If I bring my eldest into the room my youngest won’t sleep and just wants to play with them. If I just put her into the cot she just screams (horrifically screams not a fuss). I have tried settling her in the cot but the only way I can calm her down is by picking her up.

she wakes up repeatedly throughout the night and we can sometimes keep her in the cot and shush her back to sleep other times it’s picking her up. Feeding her does not work, milk seems to wake her up not make her sleepy.
Any advice for a tired mum would be appreciated

Make 3yo room safe, and with a gate to keep them in if needed. Use safe apps like CBeebies games and Yoto audio player etc (which can be operated by a 3yo) to keep her entertained.
I had the same issue with a similar age gap and a shift working DH who could never share bedtime as he was always at work. This worked for us .

My children never mastered drowsy but awake. I just put them in their cots once rocked or fed to sleep. I understand the point if it makes life easier but it sounds like it's making life hard and for what?

Thank you good idea regarding apps in a gated area. I just feel guilty leaving her each time on her own for so long.
intotally agree to keep doing what you are doing if it’s working but for us it’s not working. If we put her down asleep she wakes up hysterical about 30-45 mins later. I can’t feed or rock her to sleep like my eldest. I literally have to sit in one position until she gets to the point of almost sleep and it is wearing me down. Sitting in a dark quiet room whilst my eldest in on her own is really effecting my mental health. If I was to wait for her to be asleep it would take even longer and then she wakes quickly so I’m at a bit of a loss. I’m trying to think of ways to help her feel comfortable in her cot.

If she is taking an hour to get to sleep that would suggest she likely is not actually tired enough to start off with. I would push bedtime back to closer to when she is actually dropping off fully - so pushing back by 30-45 mins. As long as the circumstances are appropriate for sleep eg dark room and quiet, babies should be able to drop off within 15 minutes or so if adequately tired and being soothed to sleep by the usual method for them. Personally I would not persist with trying to get her to go into the cot awake and drop off but it may work better if she is actually properly tired.

Could you switch the timings so you do the 3 year old’s bedtime first? So you do bedtime routine, books etc for 3 year old with baby in your arms, fed or whatever, the leave older child in bed with nightlight, story playing or whatever.

Then focus on getting baby to sleep? May work better as a bit later, as well.

What are her daytime naps like because I found that crap day sleep inevitably meant a shit night also