Need some help

If my parents are divorcing and my dad doesn’t allow my mum to have some or all the dogs where does she stand with that? Obviously they’re both their animals so surely he can’t deprive her from having them/some of them?

We have 4 and at least 3 of them cannot be split up. 1 is quite an unsocial dog so she would cope alone.

My dad has never done anything to look after them apart from walking them with my mum sometimes. My mum is the one that feeds them, gives them their medication, takes them to the vets etc etc