Jenna's mom found out about a big sale that was going on at a mall near them on Jenna's birthday and told her about it and thought she could take her there for her birthday.
But, Esther's dad [also Jenna's dad] found out about it too and wanted to take Esther for her birthday too and didn't know that the mom and Jenna were going to be there.
After they both got to the mall AND in the same store, Esther's dad, their parents [still not knowing that each other are there] decided to look around as well as the girls. When they saw each other they were confused for awhile on why they looked so much alike, then they started questioning each other about their parents and they were wondering if they really were sisters or related some how.
When their parents found both girls their and each other they were both exited and mad.
They told the girls to go look around at stuff in that store and the parents talked about what to do.
After a while of talking they decided just to leave and go home.