Toddler behaviour

[InsideOut91]

Looking for advice on anything I haven’t tried yet!
I have a 2.5year old girl, she’s amazing but has understandably struggled with behaviour since the arrival of her baby brother who is nine weeks old now.
Theres one thing I’m struggling with in particular in terms of behaviour, she’s a very loud child and always has been but in particular every time her brother is trying to sleep she screams at the top of her voice, every time. He struggles already because he likes to be held to sleep and I can’t physically do that all day long because then I can’t give her any attention at all, so if I manage to actually put him down asleep then she immediately wakes him up.

I’ve tried:

getting her to sit with us and I can read her books whilst I’m sat with him.

telling her when he’s asleep it means mummy can actually play games with her because I don’t have to hold him.

explaining about her indoor voice and how it’s not kind to wake him etc (she has great understanding)

taking them out so he can sleep in the pushchair but that doesn’t work as he won’t really settle and even at the park she still needs help with swings and climbing things so I can’t constantly push him around.

taking away privileges such as tv time etc

And the thing is, it’s something every single time I’m sat feeding him, she knows I can’t really get up so she’ll intentionally break things or lick things (which is her newest thing). She thinks it’s hilarious and realistically there’s nothing I can do to stop her but it’s also not something I can ignore when she’s breaking things and licking furniture getting countless germs in her mouth.

I know it’s normal attention seeking behaviour but I’m at my wits end about how to deal with it in the moment because nothing seems to work.

one day I even got so frustrated I put her in her cot whilst I sat in the rocking chair feeding baby in the same room and told her it was because I couldn’t trust her not to misbehave whilst my hands weren’t free. She screamed and tantrumed but after a few minutes she just started using her cot as a trampoline and didn’t care at all.

My two are about the same age and it's a similar situation, so I sympathise. I find having the baby in a sling helps. He tends not to wake up in the sling when the toddler yells and I can do things with the toddler at the same time as holding him. I try to get him a few good naps in a day and then later on, when I'm tired and need to put him down, I just accept he's had a few good naps and now he's having a few poor ones.

I try not to sound too interested by the things the toddler does to make it a bit boring to bother doing again. Mine likes to pour her drinks on the floor so I might say "What a silly thing to do. Now your drink is gone and the floor is all wet and slippery". Sometimes I can get her to tidy the mess up herself.

Thank you ☺️
Yeah my instinct is to ignore or act uninterested but unfortunately she’s clever enough to know to do things I can’t ignore! I know it’s normal and I know it’ll improve I just don’t want to constantly shout and lose my patience with her, I’d love to find something that works. For the baby also, I don’t want him to just hear me shout over the top of him all the time!
I guess it’s our own fault for having this age gap haha, should’ve waited until the older one is old enough not to want my attention anyway 😂