Though the Emperor had always favoured the Fifth prince, it doesn't mean that he did not share his love with his other sons and daughters.
They are all his blood related kins after all. How could he not love the flesh that came from him?
When he saw his son using coquetry on him, he was visibly so happy with his smile so wide that it looked like the corner of his lips may reach his ears.
How can any Father not like his kid acting cute with him?
Thus with a huge grin, he nodded his head, "Of course, of course. How can I not cheer for my son? I will definitely cheer for you. Now go and perform the best you can. Go! Go!"
The Seventh Prince too grinned like a cheshire cat once his Father agreed to cheer for him.
He started humming for himself as he walked away from them towards his cheering squad. Every step of his has some energy to it making it very obvious to know that he was very happy now.