My 4mo old HATES tummy time! FTM help :(

Emily

I have a 3, almost 4month old (a week away) and he HATES tummy time! He has since he was born, and he ONLY tolerates it if his chest is propped on a Bobby, a pillow, an arm or leg etc.

I’m worried and feel bad because my sister said he has a weak back? And need to be on his belly regardless on if he likes it or not to work his back out, so she put him down on the play mat on his belly and LIKE ALWAYS he started screaming!

Am I doing something wrong by propping him? Is he not gonna develop correctly? Should I just leave him on his belly when he starts crying? I have no idea :( He holds his head up super well, can look up at me on his belly, easily moves his head around, so I don’t know :( he shows no signs of rolling yet.

Please give me some advice.