I adore
Poppy. It's an uncommon flower name that doesn't get lost among the sea of others with flower names. It has a nice sound to it and poppies are quite a lovely flower to be named after. :) I would totally use it.
Of your combos,
Poppy Eleanor and
Poppy Madeleine are excellent! I like
Evelyn Poppy (and
Amelia Poppy) if you wanted to use
Poppy as a middle name.
Of the sibsets, all the boy combos except for
Poppy and
Remus sound great.
Remus and
Poppy clash to me because
Poppy is classic-chic while
Remus is a more eccentric, off-beat choice.
Of the girls,
Poppy and
Grace and
Poppy and
Eleanor are nice choices.
Also, how about
Poppy and
Sebastian,
Poppy and
Abraham,
Poppy and
Silas,
Poppy and
Charity,
Poppy and
Louisa,
Poppy and
Clementine,
Poppy and
Helena?
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