no, I normally teach sideslipping in an intermediate or advanced intermediate lesson, to aid with learning hockey stops, speed checking, improving parallel skills etc.
first off get her used to walking in the boots and try walking in: a. pizza shape b. duck foot c. sidestep
for her very first time sliding, go to an area with a very slight slope with a long flat or uphill after it, and practice a french fry slide. next slide, throw pizza into the mix. in this case teaching sideslipping would count as "french frying when you're supposed to pizza"
when she seems able to stop, move onto slightly steeper terrain. when she's able to stop on steeper terrain you can intro the rope tow/t-bar, and depending on how awesome she is, you could go for the lift. gotta be able to read your student though--if she's stuck on something, try something else. speed the lesson up or slow down depending on how bored or upset she is, or simply take a break.
the most successful of my students have all had one thing in common, a good attitude. even if they fell countless times trying to pizza on the first day , if they had a good attitude about it I could generally have them shredding blue runs on the second day.
next is overall fitness, but a good attitude is probably more important in beginner skier success than fitness/coordination.
it also helps if she's done sports like biking, ice skating, rollerblading, etc... even wii ski. haha