Hard poop? Helpppp

Alantra🧜‍♀️ • Wife ❤ 1 son 💙 One on the way with a twin in heaven 💕

My son is 6 months adjusted and has had poop balls for about a month. I didn't think anything was wrong with it because he's my first. But my step dad said he shouldn't be pooping in solid balls yet. He's 9 months old from birth. My niece is only 12 days older than him and she's eating table food and not pooping solid yet. Should I be concerned enough to bring it up to his dr?