This is creative. I like it. I like the fact that your dragons were not alone in the world and they each found happiness. Then the attractions begin in that everyone wants to come and see the dragons. Do the dragons get some profit for being a part of the festivities?
It started with a picnic, where they got married and then had kids and shared their lives with the people in the kingdom. They were not scary dragons as some would have created.
The rhyme of this poem was easy to read. I definitely would let my children read this because it teaches them to work together with those who are different. Find your common ground and you can get along. Did the whole dragon family join in the festivities or was it just kids or just parents?
The flow of the poem made sense. It probably could have used another stanza of description after the kids sell the squid because you don't know about the parents.

There one stanza that I would try to reword the last part of "A ring was placed upon her toe..." The wording in the last two lines does not quite fit although I understand what you are saying.
Keep writing.