No babbling

Okay so my son is 6 months old. He doesn’t babble. He makes noises and blows raspberries when he’s excited but no babbling. He is very alert, makes eye contact but no babbling. He doesn’t sit up unassisted either. He will sit maybe for like a minute and fall down. Do I need to worry? Also, I found out in my absence he’s been watching tv. Little baby bum specifically. I wonder if that is slowing down his growth? Do any of your babies watch little baby bum? My son is obsessed.