Semi-mobile baby sleeping alone in bed - safety issues

[Zimbah]

My just 3 month old DD is attempting to roll from back to front, and has just learnt how to spin round in the same spot when on her back.  Obviously her mobility will only increase .  Her cot is side-carred onto our double bed.  When I'm in bed then I don't worry about her safety as I am aware of where she is in the bed, but I'm not sure what to do about nap times and if she starts going to bed before I do.  She's a big baby, almost too big for her moses basket so that won't be an option for daytime naps for much longer.  I would like to be able to leave her in her cot (with frequent checks) when she naps in the day, but don't know how to make it safe.

I've thought about putting pillows around the edge where the cot joins our bed but I think that would be a suffocation risk if she rolls up against it.  What do other people do?  This was never an issue with DD1 as she only slept if I was there with her, whereas DD2 thank goodness seems to be a much much easier sleeper

[SweetSilver]

We had a queen-size futon on the floor when our dd was about a year old.  Before that in a different house our strapped-to-the bed cosleeper was on one side, the other side (dh's) was pushed against the wall.  This was a  futon on a frame on carpet, so we had no problems with the mattress sliding away from the wall, which could be a hazard.  In a tiny house like ours, I could keep an eye on her from every room.  But she wasn't too rolly until she was nearly 1yo.

[winterbabymama]

This was my concern too.  My DD is now 8 months old, and we just took the sidecar off our queen size bed, pushed the bed against the wall on my side, and now she is only in the bed when I am. Which means naps and the beginning of the night she sleeps in a pack-n-play.  Not what I wanted, but she is a mover and a shaker, and she'll roll herself right out of bed in no time.  I did use pillows to barricade her in the sidecar for naps from 5 months on, when she was able to hold her head up while on her tummy (before that time she wouldn't nap without me).  We do have the humanity organics pillow and bed sheet, which is nice for one side, but isn't enough for her to be in bed alone, and I don't think the bed rails would be sturdy/safe enough to leave her alone either.

So I'm not very helpful, but I am curious what other mommas have to say.

[cww]

Wondering about this, too.  We have an almost 7 mo old who so far naps always in the detachable stroller/car seat in whatever room we are in, and at night sleeps with us in bed.  Even with a mattress on the floor, I don't want to leave her alone, since if she wakes up she will quickly crawl/roll all over the room and get into outlets, eat dust bunnies, play with the laces on shoes, etc.  (Apparently I was prying off those safety covers in no time as a baby, so I don't feel like "babyproofing" is really something I can depend on when we are out of the room, especially since I'm always discovering new things that might be a choking/electrocution/drowning/strangulation hazard that always seemed harmless in life pre-baby).  If she isn't strapped in, she can crawl out of the car seat on her own now, too. 

It's not an ideal solution, but for us strapping her into the car seat for early bedtimes or naps, either in another room with the door open so that we can hear her, or just with us (with white noise to block out our noises and the shade up to block light from her eyes) has worked ok up until this point.  But I'd love to hear other people's suggestions for as they get even older!