Handling a new puppy with an older JRT also.

In a few weeks I will be bringing home my new female JRT Zowie! I already have a 16 monrh old male JRT who is wonderful. He is fully house trained and is left out in the house during the day while I am at work. I stopped crating him about three months ago. He never destroys anything and his behavior is exceptional.

My question is - when I bring the new puppy home and crate her during the day, is it okay to leave my other JRT free in house as usual with the puppy in her crate with my other JRT around her or should I place the puppy in another room where my JRT cannot see and get to her? I fear that if I separate them my JRT will spend the day trying to get to her in that room and be obsessed over seeing her as he is obsessed enough already. Another alternative is to crate them both together but I don't think it is fair to starting crating him again when he did nothing wrong. He does not need to be crated.