Can she sit unsupported? If she can then it's ok to start solids. My baby could sit unsupported around 5.5 months so we started solids. She started standing up and make little steps supported at 7 months but only started sitting up on her own around 8mths. So yes, every baby is different in their developmental milestones. Have you tried making the puree with breast milk/formula milk? May be easier to introduce with something she's familiar with
Clarissa Lim