Really depends on the weight of the tt and how much weight in the SUV. Casitas are pretty small and light, so if it's just her she could get away with any of the newer V6s like a Toyota Highlander or Ford Explorer for example. If the SUV will be loaded with passengers, the trailer over 4K loaded or a lot of mountain towing, she'll want something with a V8 and more payload like a Tahoe/Yukon, Sequoia (they are essentially trucks) or a Durango. Really hard to say without more specific info.