Cosleeper cot with a moving baby

[blushingmare]

I have adapted a normal cot to make it into a cosleeper which is where DS starts the night before coming in with me at some point during the night. The mattress is raised up to level with my bed and one side is taken off.

But he's 6mo now and it won't be long before he's rolling and then crawling & pulling up to stand What do you do about cosleeper cots once they're on the move?

Bumping. He's starting to roll now!

Bumping! We have a bed rail for the other side of our bed but its not really enough now we have a 1 year old. Think I have read about people going to mattresses on floor but not sure DH will go for the "crack den" vibe

No puggle, mattress on the floor definitely not an option here either. Hoping someone offers an ingenious solution - it must be a common enough situation.

We put back the 4th side of the cot which was earlier removed & positioned it such that the 'drop side' was closest to our bed. It did mean hauling over it to pick/ put baby in, but it was the only way to prevent any accidents. When DD was 7 months old one night I found her at my knees...and nearly about to fall off my bed! That was the last night without the 4th side of cot!