Since having a baby 6months ago it's become dry, brittle and very frizzy.
It's naturally curly/wavy and thick, always a bit unmanageable so it's layered and graduated at front.
But now it's so knotty I keep having to cut out the knots! I tried dying it to disguise the dullness but dye didn't take well and it's worse than ever. It's also getting thin at front and hairline is receding 
I don't want to have it cut short. How can I make it look and feel better? Is a Brazilian keratin treatment the way forward?