I'm running a group of five through the 5e starter campaign (Lost Mines of Phandelver), and I'm going to be in a position to add another player. I don't want her to have to wait until we move on to a different campaign, and we're currently in a spot where adding her wouldn't be difficult, from a story perspective.

My questions are these:

1 - Would adding her in alter the balance too much for the campaign, since it was designed for (up to) five players

and 2 - She would likely be playing a bard, but I'd be starting her off at the same level as the other players are currently at (Level 2), how should I go about giving her stats/skills/equipment? Roll for the stats and use starting equipment for the class, or some other manner?

Thanks in advance

Roll the stats, and I believe 5e has a wealth by level chart.

So, you give her the starting gear and some extra cash to buy gear.

As for balance, just toss an extra monster in there. I'm running Ravenloft with 8 characters right now. Just toss a few more dudes in there and it should be fine.

Plus, you're the only one who knows exactly how many HP a monster has, and you can use that to the advantage.

I would run it as is for at least a session, test how much easier it feels for the party?

Then make a decision once you’ve got a sense of it yourself.