Curve in spine ?

[Jezzabells]

My child is unable to sit up straight without leaning on floor with hands. Gp has said it's habit however his spine sticks out alot at the bottom. Should I seek second opinion?

If you Google how to teach a baby to sit unsupported there are lots of videos, you could see if there are some tips to help that you haven’t tried yet.
If you mean you can see the spine, because there isn’t a covering of fat, my skinny teen looks like that if hunched over.

My daughter has just been diagnosed with scoliosis. She is 11 so it’s bit different.

i would definitely get it checked again though if you are concerned. It’s rare but some babies do have scoliosis.

it’s a bit hard to see from your photo though

Doesn't look unusual to me, but that's just my amateur opinion. Sitting up self supported used balance and core stability muscles... Does your child do much physical activity that might develop this? Some kids are just in constant motion and always doing something, others are content not to and need encouragement.

For anyone who has this situation,
take your child to a chiropractor.
chiropractors are able to tell way better than any other doctor whether your spine is out of place or not.
I love chiropractors.