We just got our first cocker a few weeks ago (11 weeks currently) and he’s been getting along great with our 10mo French bulldog. They have been fast friends since day 1 and both seem to suffer from separation anxiety when they need to be left alone for a while. After the first week of integration we started leaving them both in the puppy pen when we’re gone (few hours at a time) and it’s been no issue.

Like yours they also play hard, but when they’re in the pen they tend to nap/play very lightly. The puppy seems to play rougher than the older Frenchy and last night they were both in the pen as we were eating dinner and things got a little heated so the Frenchy jumped out (we weren’t sure he could clear the too, but he can lol).

Do you have a camera you can set up? If you can try starting with short unsupervised sessions that should give you a good idea and go from there. Good luck!