Aw Tammy, how great of you to actually take a vacation! I am sure you are excited!
Since you are leaving Tillie with another hav owner, I am sure there is not much to worry about, though, having home-cooked meals for Tillie for a while now, that would be one thing... how *are* you going to deal with that?
When I left for Paris and had to leave Cey with my neighbors for 11 days, I was a wreck too. They were not at all familiar with havanese dogs and in fact are not even dog owners, but, they love Cey to pieces and are really good, thoughtful, kind, and respectable people so I knew I could trust him with them, and also and most importantly, that I could trust them to follow my basic instructions about feeding, watering, care, etc.
I just left them 1) his crate, 2) his food (also his food and water bowls), 3) a variety of his favorite toys, chewies, etc., 4) his shampoo and conditioner, 5) his combs and brushes (even though it was another neighbor that was going to be combing him out - long story but basically she was familiar with grooming animals and they weren't, and she had already offered to groom him whenever I wanted, and since we all live next to each other in the same courtyard it worked out perfectly), and just really basic instructions about how I care for him (what I do with him when I am not home, his feeding schedule (or lack thereof, since he free-feeds, but same idea), how often to bathe him, etc. Oh and of course his harness and two leashes, one regular and the other a flexi-lead. And the address and phone number of his regular vet, and the emergency vet they should take him to after hours if anything happened when his regular vet was not at work, and of course my phone number while I was traveling. Whew, do I sound like an overprotective mother yet?!
Anyway - as you are leaving Tillie with another havanese owner, you should have a lot less to worry about in general that I did
. As long as you have communicated with the sitter about Tillie's schedule and what she is used to (crated at night vs. not, feeding schedules, etc.) and give them basically everything physically important to what might make Tillie feel more at home there (crate, toys, etc.) then I am sure she will be fine!
In fact, I bet she LOVES having two live-in playmates while you are gone