Well, if she doesn't mind training with it, as it's tough to shoot at first (light weight + small size = large recoil) I love my LCP. The LC9 has much better sights, not to mention you get to stay with 9mm (as she has the G19). However, I doubt the size difference between the LC9 and the G19 is that much. I've carried the LCP with a supertuck deluxe and LITERALLY forgotten that I had it on even while driving.
I will say that laser sights for it really are a must as the sights are a joke. If the LCP is too expensive then check out the Taurus one (can't remember the name). It has a mag that holds the bolt open on the final round, which is nice (the LCP doesn't) and it comes with a neat little holster. The KelTec P3AT is also a good choice. All three of those are basically the same.
I would recommend checking which of them the crosbreed super tuck deluxe is available for as that holster is sweet! Or the mini tuck too.