Is your baby sitting up unsupported?

MamaBear3 • I’m not like a regular mom, I’m a cool mom.

So my twins just turned 5 months on the 28th. They roll from tummy to back and vice versa all the time. They sit in walkers really well with great head support. but they aren't sitting up unsupported yet. I know all kids are different just wondering if they aren't the only ones not doing it yet? thanks mama's!