Help downloading packs for my kid on a child account

Hi folks.

Can anyone let me know how to also this? My 7 year old plays dimensions on ps4 on his own login (not psn) but because he is 7 he doesn’t have a psn account. I have one but the option to download isn’t in the game.

How slides he download the packs? Do I need to play half the game on my login and download them from there???