Ok, I have a few things.
1. Bring an NPC, but make sure that she's making the calls. Keep the spotlight on her, never your character. Make a character to balance her's. D&D 'roles' aren't really a thing anymore, but you do want someone who can take hits, someone who can dish out the hurt, and someone who can heal the injuries (this doesn't need to be a cleric - paladins, bards, clerics, some warlocks, some sorcerers, druids, and any human human who takes the Magic Initiate feat can heal. Tip: Healing Word is your friend. It doesn't do a ton, but it can be cast in combat as a bonus action, meaning you don't have to waste a round to heal someone.
2. Boost the PC. Low levels are fragile. There are a couple of ways to do this. First, use point buy and give them a few extra points (say, 30 instead of 27.) Second, the rules say you get your full hit die worth of hit points at level 1, then roll afterwards. Instead, give them max rolls up until level 3, then guarantee half afterwards (at level 4, if you get a d8 hit die and roll 1-4, 4.) If you want to go to extremes, give characters their level 2 hit dice at level 1 (they get two hit dice worth of HP at level1, but none at level 2.)
3. Give her a companion.
this is a fantastic rules supplement that I've used in two campaigns, and I've been a player in a campaign with it in use. It treats companions (say a bannerman, a squire, a pet baby griffon, whatever) almost like an item. Instead of a second character sheet, the companion is assigned to a player. That player gets a card that lists, most of the time, one extra ability plus a few health boxes. Say you have a man-at-arms companion. He isn't on the board. There's no extra miniature. But when the player he's assigned to attacks, they get an extra d4 damage (representing the extra attacker), and a blow aimed at the character may be taken by the companion instead. It's a simple and elegant way to handle hirelings, cohorts of troops, or whole gangs of escape prisoners working with the party without bogging the game down.
4. Rebalance the encounters. Skip the math.
Kobold Fight Club is your friend.
Ok, now, don't do all of it. You'll create a monster. Instead, pick-and-choose. Personally, I'd add a GMPC, do the full hit points per die through level three (or maybe four), and maybe the companion system. Then tweak the encounters slightly in advance with KFC. If you don't want to buy the companion system, then increase the point buy.
Some other quick tips for those without accessories.
None of these are mandatory to play. If you want these things, go, here are some quick options to get you started without a ton of cost.
1. Search for the names of the maps ("cragmaw hideout map") on Google Images. Every official adventure has had stacks of player-made maps that are more attractive than the ones that are in the book. They're free. You can set them up on a laptop, spare computer, or print them out if you like.
2. Miniatures. Everyone knows I've got a miniatures problem. And yet getting enough miniatures right off the bat is an expensive proposition. There are a couple of cheap options, though. The first is Pathfinder Pawns. They're created for a different games, but it's a D&D spinoff game so most of the same creatures are represented. The Bestiary Box plus maybe a set of characters would be plenty to get playing. The other alternative is printable paper miniatures. Just do a search.
3. A surface for playing. There are several options. Gaming Paper is the cheapest (that's the brand name), and if you have a cheap Wal-Mart poster frame (or just a sheet of plexiglass), you can put it in there on top of the table and use dry-erase markers on it forever. As a side benefit, you can put pre-printed maps or paper poster maps in the poster frame to make it work with dry erase. Second option would be an easel pad with a 1" grid from an office supply store. Basically a poster sized graph paper pad. You can draw maps in advance and toss them after they're used. Another option (likely the best, and not much more than the others) would be a
Chessex Battle Mat and a set of wet erase markers (wet erase, never dry erase for this.) It'll last you a lifetime. I still have the one I was using in high school.
4. Dice. You have a set from the starter set. You may already have some of your own. If you need more, one cheap option (and a classic) is the
Chessex Pound of Dice. If you only need a few, consider letting her pick out a set that appeals to her (especially if you have a local gaming store she can pick out a set from.) Having a personal set of their 'very own' is a great way to get kids into the game.
5. Don't ask for D&D advice if you don't want be inundated with tons of D&D advice.
What doesn't kill me makes me stranger.
Leaves me with two extra sets, plus the one that came in the starter set, so I think I'm good there. Probably need to pick up a GM screen at some point, but we'll see how this first session goes first.
