Can I retrofit blackout lining onto a blind

[DistractMe]

Is it possible /practical to add blackout lining to a roman blind that was originally made unlined? The room wasn't originally used for sleeping, it is now and the early morning sun hits the window full on. I like the blind and I want to be able to fix this without spending lots of ££££.

Unfortunately the original maker is no longer in business, otherwise I'd ask her.

Is the current blind inside or outside the recess? Honestly if it was outside I would install a blackout roller blind behind the Roman blind and pull it right up behind the current blind when not in use.
it is possible to reline the Roman blind but it involves a remake and the full cost of that.

It's in the recess unfortunately.

Use a stick on velcro blackout blind behind the roller blind.