Hello and welcome to Binky Bunny! You will very soon need to separate your bunnies, as they are approaching puberty and you will be dealing with surprise litters if they are kept together much longer. You can also be dealing with fighting and injuries. You may want to go ahead and separate them now, just to be safe, instead of waiting a week or two. After they have had their spay and neuter surgeries, and a month or so has passed, you can start the permanent bonding process. Until that can happen, don’t even let them out for play or exercise at the same time. It only takes a few seconds for a pregnancy to occur. Some people don’t even see when it happened.
Here are 2 good articles on bonding. Your bunnies only have a temporary baby bond now, not a true bond. That will only come after spay and neuter and a bonding routine.
http://rabbit.org/faq-bonding-multiple-rabbits/
https://binkybunny.com/BUNNYINFO/tabid/53/CategoryID/9/PID/940/Default.aspx
Bunnies like to pee on soft things, like beds. It’s best to keep them off of there until they have been litter trained. It’s usually not too easy to completely litter train a rabbit until they have been spayed or neutered.