I use Parental Control Bar. It's free. It doesn't have a keystroke logger, but you could block sites that she could be setting up passwords for. The only problem is if you use Mozilla/Firefox, last time I checked it wasn't compatible with the most current version. I tried to go back to the older version and couldn't get it to work, so I just uninstalled Firefox on the computer the kids use. Biggest problem I have had (not really a problem, shows its working) is the kids complaining about it blocking a site, and turns out they had misspelled the site name. That kind of thing is the main reason I got it, so easy for kids to misspell and stumble onto something they don't need to see.
The best ones with a logger I have seen are either around $100 or $40-50 a year subscription. There are also little devices you can put on the keyboard connector, that are keystroke loggers, but I have never checked into how much they were. Just heard about them from my IT guy at work.