[He jumps in surprise at the sudden chocobo head, but he doesn't think anything of it as he moves to pet her head like he would any sort of domesticated animal. It's not so much of a surprise that Grell trusts him, but more the fact that she's put thought into this.

If he thought about it himself, he'd realize why on his own. Aunt Cass had Mochi available for her nephews to help them calm after the death of their parents. Having Baymax to look after, having a project to work on and something to distract him definitely helped calm him after Tadashi's death. Without those here, his life had been sort of up and down until recently. So yeah. It made sense, but he didn't think those were Grell's intentions.]

I'm not. Worried, I mean. Lumina showed me her care guide for the chocobos last fall and I've been to the ranch before...they're kinda cool birds. [Considering he's much more relaxed, maybe that "kinda" isn't necessary.] I'll take care of her. We'll be fine. [He's still caught in the "what????" of it, but the idea's more appealing the longer he thinks.] Thank you...for trusting me, I guess.