I am so sorry for your loss.  Yes, the estate can make arrangements to allow the occupants to remain rather than evicting them, given the circumstances here especially.  It is really often better that a house that belongs to a decedent be occupied to protect it from vandalism during the probate process.  There will be some point in time where they house will need to be cleaned up to be sold and any buyer will want it delivered vacant.  You can also make arrangements for rent, utilities, etc., while they occupy the house.  This way the two that do not live in the house will not feel like they are being taken advantage of in the meantime.  Good luck.