To the OP...have you thought of emulation? I mean, there are plently of games out that a 7 year old girl would like if exposed to them. Try getting her a SNES or N64 emulator and a few ROMS...Sonic, Mario, Zelda...all excellent games for the younger crowd.
These games are sneaky...most girls think "no" then end up loving them.
Perfect example is my girlfriend...she really liked all those "mystery" and "puzzle" games but soon ran out of games to play...my remedy? I said, "Here, try this Zelda game on the old n64 using the computer"...she said, "that sounds gay...I dont want to play Zelda"...now one week later shes almost beat Ocarina of Time and is excited to start playing Majoras Mask.
I really recommend emulation and ROM's...may seem kind of whack and cheap (considering it free, if not you are looking in the wrong place) but a lot of games are still pure gold and offer a lot more polish and overall better gameplay/experience compared to PopCap games and the like. I mean, take Zelda on n64..sure its free now and may make it seem cheap...but back in the day it was a $60 game on a $200 console that had 99% positive reviews...NOTHING wrong with that lol.
Let me know if you want some info on obtaining the emulators and ROMs...its so easy! Plus a 7 year old can figure it out...its not technical at all...you open emulator software...go to file open ROM...select game...hit start...bam game starts playing...simple as that.