I recommend thinking about opening her an account with Alaska Airlines instead of American, even if she'll never fly Alaska. If she doesn't fly enough to earn status, there's no reason for her to stick to American for her flying, and Alaska lets her credit miles flown on both American and Delta. That should help her build up to a usable number of miles more quickly (and still allows redemption on most of the oneworld and SkyTeam airlines that fly to North America).

There are some caveats, particularly on the redemption side (mentioned in several other threads), but worth looking into.