Petticoat or slip. Is one needed?

I agree with the majority, you look great as-is! You don't need to add anything, so just leave it up to your own preference and comfort.

This looks beautiful on you as it is! Unless you want crazy princess look.

Hoops act as a little ac unit while you walk. as for a slip only get one if you feel you need an extra little layer

You can probably take your dress to the store where you bought it and ask to try it on with a petticoat. That would give you an idea of how much poof it will add.

The dress looks beautiful without a petticoat. Getting one would depend on it you want a fuller type of dress. I don't think it needs a slip at all.

I wouldnt get one your dress looks nice on its own!

I have a petticoat for mine. It added to my dress and gave the illusion that I’m just a bit thinner lol. Too bad it doesn’t make magic happen!
Your dress looks great as is but if you feel like it I would try one on underneath. Congratulations

If you want a pouffy princess dress definitely get a petticoat otherwise it’s not needed. Your dress is gorgeous

You don't need a petticoat or slip, your dress is lovely as it is. It just depends on how much 'pouff' you personally want and how dramatic of a ballgown effect you want. I personally bought a petticoat for my dress because I really like pouff and wanted to feel princessy