Poppy Elizabeth Poppy Alexandra Poppy Catherine Poppy Charlotte Poppy Genevieve Poppy Josephine Poppy Madeleine
I like Poppy. I don't see it as being any different to other "sweet" names that are popular: Lily, Daisy, Rosie, Millie, Mia, Lottie, Emmy etc. Your child will make their name their own, so while Poppy might seem cutesy objectively, it doesn't mean that your child will appear babyish as an adult.
I don't see it as remotely similar to Pippa or Philippa .
My Poppy is Poppy Louisa Elizabeth.
All three of my DCs have names firmly in the top 100 & yet none of them has ever had another child with their name in their class/form at school. We loved all three names so we're prepared to take a chance on there being a few about, but it really hasn't worked out that way.
There are three little Isla's very locally though.