After repelling the attack on Canterlot, the ponies were able to catch Chrysalis. For a very long time, her fate was discussed, until Pinkie Pie proposed a crazy solution: To turn the changeling queen into a child.

Despite the absurdity of such a decision, it was made and the newly minted filly was taken under the care of Princess Cadance, who is surprisingly very gentle to Chrysalis.

Just yesterday was Hearts and Hooves Day, and because of this, Cadance is just overflowing with love. It's good that she has a 'daughter' who is able to absorb all the extra love.