Ava Mueller

Ava Mueller is the younger sister of Logan Mueller in Power Rangers Dino Charge.

History
She first appears doing a Maori performance for the museum with some other girls. After the dance, Ava meets Logan's friend and co-friend, Heather Merrill, who takes an instant liking towards her. When she and Logan attempt to spend time together to go to the skate park, Logan is suddenly called to battle. He asks Heather to keep an eye on her and she agrees as he runs off. When he comes back, the two finally go to the park with Heather, only for him to be called to a meeting with the rangers and Prince Richard III. As Logan leaves, he ask Heather to look out for her again and she agrees for the second time. Ava tells Heather that she has a present for Logan and the two follow him, only for the two to be caught in a battle with the rangers against Fury, a squad of Vivix, and G-BO, Richard's robot, who was reprogrammed by Wrench. Fury orders the robot to attack Ava and Heather, only Heather shields Ava from the attack and is injured in the process. Richard saves them when Logan is overrun by Vivix, bonding with the Graphite Energem in the process.

After the battle, Logan starts teaching Ava how to skate and an bandaged-up Heather joins them. Ava gives him his gift; a plane ticket back home to New Zealand so he can visit. She then goes home with her family.

She does eventually return as she's preparing to celebrate Christmas, not really minding how Christmas is seemingly cancelled, because of how Logan will be returning home.