A few years ago a small water stain appeared through my lining paper (it was a dark colour paint so you couldn't really see it), I had the problem fixed and forgot all about it. I have just redecorated my living room, again putting up lining paper and painting it with a light colour. I have noticed now that the stain is showing through, what can I do about it? Would a darker colour cover it? I would really rather not have to strip the lining paper off and start again. Any suggestions greatly appreciated. Thanks.