I recently posted the following reply re 16 month old speech. I don't think you should worry, and as long as she understands and responds that is probably the main thing.
QUESTIONS : Is she happy? Does she play with dolls, teddy bricks?
Herewith my other reply:
Oh Dear!! You poor mothers; why do you have to think you are "doing something wrong"? And she HAS NOT "fallen behind"!
It sounds to me you are doing everything PERFECTLY! Only babies don't read the developmental instruction book, so they don't do things when people want them to!
Our DS didn't walk at that age. There are NO hard and fast rules on when things happen, only broad generalisations on ROUGHLY what the AVERAGE baby will do at certain stages. I don't know what the 'leeway' on these things is (though I could probably find out, if you wanted me to.)
Just relax, and enjoy every moment of your time with her, (and it sounds like you do), and every little step in her progress. I wrote a 'diary' of DS progress,
Does she have access to paper and crayons, so she can 'mark make'? Sand, water, Duplo bricks to learn colours, counting, building towers - and knocking down, dolls and teddies. Keep TV and 'screens' to a minimum. Look at flowers and leaves emerging, listen to birds singing, and enjoy the sun shining.
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If you can answer my queries, I'll look back sometime and see how you are getting on.