B.M.
You have the right idea. I know it will be a harder transition because she is older, but it is worth starting it now. If she is a self-calming child (i.e. when she cries, she usually calms herself down quickly) then you should have no problem letting her cry it out. Consider putting music on while she learns to put herself to sleep. The noise might distract her. I can't imagine that the parents would have a problem with this. It's just what is going to work for you & if this is the only way to get it to work, so be it. You can always start out with a time limit, too...only letting her cry for 15, and adding 5 minutes each day until she gets it. I am the same as you...we started while the boys were young & now they go down, no questions asked. Good luck!