父親が、娘との絆を深める為に、娘と同じように体操を始める様子です。
父親は、失敗しても諦めずに挑戦し続けた結果、体操の技に成功すると、父親や娘も息子も嬉しそうです。
Translated from Japanese by Google
It seems that the father started doing gymnastics like his daughter in order to deepen the bond with his daughter.
The father, his daughter, and his son will be happy when he succeeds in his gymnastics as a result of continuing to challenge even if he fails.