Please translate a couple of words? :)

[dazexxx]

Could someone tell me what the big writing on his drink says?
The photograph is of the candy version, I think

The second part of this one is different?

 

[Majestic]

Gun Gun Milk and Gun Gun Yogurt

 

[Lothor]

Maybe someone with better Japanese than me can confirm this, but gun gun means to rapidly grow up and grow strong.

 

[Lomaster]

I think ぐんぐん implies steadiness. But again there's no better way to translate it other than Gun Gun Milk. Steady milk anyone? バウムクーヘン is not translated into japanese as 木ケーキ

I'm watching the first season of Haykyu currently. Nice pick of Kageyama drinking Gun Gun milk here.

 

[Majestic]

ぐんぐん(グングン)とは - コトバンク

Rapidly progress (grow) would be the correct definition here. Implying that the milk/yogurt makes you grow big and strong.

 

[Toritoribe]

The photograph is of the candy version, I think

Yes, that's right. It says ぐんぐん牛乳風キャンディ, Gun Gun Milk taste/style candy.

 

[dazexxx]

Thank you so much for your help everyone - with the translating as well as with further explanation of 'gun gun' which had me scratching my head haha I really appreciate it!