3 mo old: Using sleeping bag for daytime nap

[GirlcalledJames]

Our 3 month old sleeps wonderfully at night (7.5 hours; we are very lucky) but badly during the day. Her naps are 40 mins but if you hold her or have her in the sling or buggy they can be a few hours.
She sleeps in our bed but fairly far away from us, but she won't nap there even if you lie down with her like at night.
I'm wondering if she's being woken up by draughts, as the only difference during the day seems to be that she has a cellular blanket and not her sleeping bag.
Do you think there's any risk that using her sleeping bag during the day confuses her about her bedtime routine?
Or could it just be that being a good sleeper at night, she doesn't need to nap much during the day?
I appreciate that this is a minor problem in the scheme of things and am very happy to keep holding her to nap if that's what she needs.

Definitely use the sleeping bag in the day. If she’s used to it at night it will just enforce good sleeping habits - if you put her in it for every nap and night time she’ll soon know that being zipped in means sleepy time. And will hopefully nap better for you!

I agree. The only difference in our nap routine and bedtime routine is bath and teeth brushing. Depending what they’re wearing I’ll sometimes even transfer to pyjamas.

Though I should add at 3 months it was a bit more random. I did whatever I thought would work.

Teddy for the win!

If you use your bedtime routine for all sleeps you will eventually be able to put her down for a nap or at bedtime wherever you are, on a plane, at granny's, at a party that goes on longer than expected!

My 3rd dd was a great night sleeper but a horrible napper and an even worse car passenger. At 3 months I eventually took my mum's advice of a dummy and a blankie in the car - before then she would scream for the hour long journey to and from school and I was at my wits end and ready to put the car through the central reservation. Miraculously she slept like an angel with the dummy and from then on, plugging her up with "Dr Dodie" and giving her a blankie was like slipping her a sleeping pill! if she wanted to come out of bed the dummy came out and the blankie was left in the cot, if she still wanted them she was put back to bed and would, more often than not, snuggle back down. I was a lifelong dummy hater - I have no idea why - but am now a convert, as long as it is used as a sleep aid and not to shut them up. If a sleeping bag works for you then go ahead and keep her in one at nap/bedtime until she's ready for school!

And congrats for having her sleep through at 3 months, you're obviously doing a great job.

Thank you for the great advice!
Her sleeping through (almost) is definitely not our doing! We're lucky that she's never had colic, she's very tall/long so reached the weight boundary for going all night very early, and she's very relaxed by nature.
She won't take a dummy, though, unfortunately.