Yes it does seem to be heriditary.
My Nephews and Niece were all the same,all same family,3 boys and a girl! All the washing their poor Mum had to do!!
But she was like that too. Her DD had lots of UTI's (are you a nurse??) and after a scan,they found she had a small pocket in her bladder which held a little "old,stale" urine,which was causing the UTI's.
I think she was told to drink plenty,pee often and she'd grow out of it.She has.
All children are different as to when they get Bladder control at night.Just be aware she has a "problem" and will need slightly longer to gain control.
My DD1's nappies were very soggy and heavy,I thought she'd never be ready. I was brave one night and left them off,used lots of care mats to save the sheets,but she didnt wet the bed,and hasn't ever since(she's 3.11)
Age is important,When your DD is ready she'll just do it.
Could she use a potty by her bed at night?
maybe use Pull-ups initially,and see if she'd use Potty,and then try no Pull up(or knickers,so its easier) and Care Mats on bed.
If not successful,leave it and try it again in a few months.