Consent of other parent for H-4

[cheesecrackers]

Hi,

I am separated(not legally) and my daughter is in India with my folks. They are going to apply for her H-4 visa and I have prepared all the documents. It was no where on the forms but will they need a consent letter from my husband?
In case I cannot provide it what should I do?
He is neither in India nor US.
If I say I am separated will they need separation papers which I donot have.

Thank you,