a) If you predecease your mother and her will is not change the house goes to your children (child of a pre deceased child inherits rule)
b) If your will is leaving evertying to your children then this will include anything you inherit between now and then, because it forms part of your estate - but make sure you discuss this with your solicitor
c) Your mother should not transfer her house to you and make herself homeless or liable to pressure to move out into a home etc.
d) if your mother dies intestate, you inherit, and if you're dead, her grandchildren inheirit before your sister, so really if the home is her ownly as