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Lustre Elstar (Twilight x Applejack) and Mariguette (Holy Dash x Spike)
 

 
Although Mariguette didn’t have to work at the Apple farm, she loved helping her favorite cousin harvest apples. She preferred especially the end of the day, in order to taste the jams cooked by Lustre, and the sleepovers that followed these trying days.
 
Lustre understood soon enough that her cousin adored precious stones as a meal, which had surely been given to him by her dragon side. Unfortunately, the stones were quite difficult to find in Ponyville and Mariguette was often forced to eat pony food. It was by observing the tree of her grandparents, Pear Butter and Bright Mac, that Lustre had an idea. She proposed to her cousin to plant an apple tree seed and a crystal tree seed. However, the days passed and the crystal tree unfortunately did not grow. Seeing this failure, Mariguette wanted to try her magic, being convinced that her brand of beauty would be related to magic. When she threw a little light underground, the crystal seed sucked out the power and made the ground tremble to come out. The two fillies understood what the magic of Mariguette was for and continued their experiments, so that the two trees would give magnificent crystal apples, which Lustre made immediately in jam for her favorite cousin, who thanks to these events had received her mark of beauty !