Sounds like a great opportunity.

On my first multi-day trip with my current hiking partner, I was in pretty good hiking shape -- I'd had a lot of trips that year for some reason. We did a couple of long-ish days on the AT in southwest Virginia that left him dragging pretty hard. Then he put some serious effort into getting back in shape, and I gave up the gym to work 60 hours a week. (Not a good trade, BTW.) Now he can leave me in his dust if he wants to. (Having really long legs gives him an unfair advantage, I think.)

Our solution is for me to lead. I set a pace that I can handle, and he stays a ways behind me, close enough that we can have a conversation, but not so close that he's walking up my butt. After many conversations about this -- both before a hike and on the trail -- it seems clear that he likes this arrangement, and is happy to let me lead.

So my suggestion is to work out in advance that you'll lead. It's too easy for the lead person to just walk a normal pace, and the following person to struggle to keep up.

Good luck.