Release deposit for rent

[John Lee]

I have great tenants who always pay on time but just had an emergency this month and rent is late. They had a larger than normal deposit due to low credit score when they sign the month to month lease. Is there anyway I can release partial deposit so they can make rent payment and avoid late fee? How do I document the partial release of deposit? How do I protect myself incase later tenants move on but want their full deposit back ?