(Caveat: IANAL)

The specific property, no, probably not.

However, a child is owed “support” from both parents, normally in the form of direct care. Where one parent is not providing direct care, they can be ordered to provide financial support to the parent who is providing direct care.

If Alex and Maya have come to an agreement where Alex will provide that mansion in lieu if direct support or financial support, Maya has a claim to the property. If Alex is subject to a support order that includes providing the mansion to Maya, Maya has a claim. Barring a scenario including the house as support, Alex will owe money to caregiver Maya (or Maya will owe money to caregiver Alex) but will not owe the house itself.