[ For him, it's all rather uncomplicated. His general affability doesn't mean he automatically trusts, or feels close with everyone, but he doesn't have emotional barriers as any sort of hindrance, nor does he see them as completely impervious in other people. ]

Length of time knowing someone isn't a prerequisite for caring about them, from my perspective.

You're a good person, and a good friend.

[ That doesn't mean he personally has to be good friends with her to recognize that she is one, in general. But. It's really as simple as that for him. ]