I'd go for the Razzamajazz series by Sarah Watts. No more than 5 notes in the whole book BAGE&D & really easy & funky piano parts to play along with her as she learns. DD started on these books & reached grade 2 in 2 years.
Thanks everyone for these comments. The earplugs may yet be needed
Wafflenose I agree that she's a bit young. I'm a music teacher myself (but have never taught the recorder) and always advise parents to wait til their children can read fluently etc. However she is the youngest in a musical family and is desperate to have her own instrument to play, and is enjoying her special 'lessons' with me She's quite big for her age so I think her hands are big enough. I started on the recorder myself at about age 5 before moving onto my other instruments later. But what I could do with is an idea of good basic technique. I know which way round the hands should go, and the correct fingering, but I don't want to be teaching her (or letting her fall into) any bad habits. I'll google Recorder Magic and see what it looks like - thanks.
I used printable manuscript paper and wrote my own first tunes. Recorder Magic is a good book for littlies - I use it with Year 2 and occasionally Year 1.
Be aware that the older they start, the faster they go, exponentially. I like them to be 7 or 8 really. If she is reading somewhat fluently, rather large, and mad keen, I would probably give it a go. DD1 started at 3.7 and played in her first concert a week later. As a new 7 year old she is doing Grade 3. However, DD2 is 4.5, rather small and can only cover the first three holes, so I'm going to wait another year with her, at least.