An idea that might be considered cute ... does your daughter have a favorite doll she really loves or perhaps a teddy bear?
I'd avoid electronic toys that might be considered obsolete in a few years or so and go with a classic symbol associated with the child's childhood.
Then perhaps you can have a small tattoo that's modeled after this toy with say a scrolled banner above and below the toy tattoo with the words Love and (your daughters' name) each in their respective banner.
I'd personally stay away from cartoon hearts or photographic portraits of your daughter's face. Hearts are too common and the latter is just plain creepy.
The major question that needs to be answered mow is do you have a competent tattoo artist that can pull off the job and do it well and also just won't sell you a slightly customized clip art that everyone in the world can get.