SIDS and Deep Sleep

[Tabathan]

DD2 is 3.5 months old and recently I’ve started to worry about SIDS a lot because she’s been such a deep sleeper.
She usually has a feed around 11pm and will often sleep until about 5am or sometimes right through to 9am. Is this too long for a baby her age?
She didn’t like the dummy, I’m not breast feeding, we haven’t seemed to need a white noise machine or a fan and I have read they all help reduce the risk of SIDs. Should I try and put more measures in place?
She sleeps in a next to me cot in our room and I follow the guidance of back sleeping in a sleeping bag. I also follow the temperature guidelines for what she wears.
Also for added context, DD1 slept great at first and then had years of poor sleep! So I know it might all change from now.

It sounds like you’ve addressed the key risks - sleeping in bag, safe temperature, safe sleeping bag. As long as you’re not smoking in your bedroom or anything I think you’re doing great and wouldn’t worry.

Sounds like you're aware of safe sleep measures and you just have an easy baby, enjoy it

That was meant to say sleeping on back *

Thank you! No definitely not smoking at all.
Just get so worried during the newborn stage!

Is a long sleep considered deep sleep? Just I couldn't wake up my 6 week old once and got worried. He had only been asleep for 20 mins.

@naisspray that’s true, I’m not actually too sure whether a long sleep means a deep sleep or not.