Answer: This is an uncommon name in the plant world. I was surprised to be unable to locate a listing for a rose named Melissa, for instance.
You should be able to find lemon balm (a sweet herb in the mint family)which is technically Melissa officinalis and is available in at least two forms, one green and one golden. There is a lavender called Lavandula angustifolia 'Melissa'and a flowering bee balm or bergamot called Monarda "Melissa"; Snow Creek Gardens offers a true lily, Lillium x "Princess Melisssa" ( http://www.bdlilies.com/ind.html ); unfortunately that is all I am able to come up with in a relatively quick search but I hope it is enough to get you started. I'm sorry about your daughter.
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