The tree owner can always download it – we ask for their password again first, to keep it safe. If the owner keeps copies private, you'll see Ask for a copy instead: pick the part of the tree you'd like and ask. For example, you could ask for just your mum's side of the family.
Where to find it
Person page → the box under the card → Copy from here → Ask for a copy (when the owner must say yes)
Still stuck? Talk to a real person: send us a message, or email support@mywholefamilytree.com