I'm not joining this one with my previous one as I don't want it to get too long and it is a bit different.
I went to the graveyard to check and see if there were any eggs. None. Sent my sim to the pup to find a dragon egg, found it and took it home. She mixed in between talking about friends getting her mail and using the bathroom. She talked about friends only; and when the egg hatched it was a purple dragon. She fed and played with her dragon, Ragnor for a bit.
While she is painting I go and check the graveyard; no eggs. After a bit I go back, and there are still no eggs, but now there is a red dragon sleeping between two headstones and at the other end of the building is a purple dragon sleeping. Send her over and she can't get to them and the red one is shooting flames at her. Send her home give it a couple of minutes and send her back. And now there is a black dragon walking around. He lets her pick him up, she names him and takes him home. Go into edit and move the red and purple dragons from the headstones. Send her back and they now let her pick them up.
She now has two purple dragons, Risa and Ragnor, a black dragon, Spectre and a red dragon Keita. I saved and later on will check to see if after a couple of days (sim) has passed there are any more dragons and she can get them.
I don't know if it was a glitch or why the eggs had been hatched and there were three of them, so I am going to check two other games in that town and see what I can find there.