If the deed is in your name, you are under no obligation to provide for your siblings, especially if they waited this long to challenge your right to the house, as reflected in the deed. They will be hard pressed to prove any alleagtion that you 'coerced' or 'influenced' your mother'. However, the fact that you did become her (legal) guardian may be the only reason the court seeks to have you share the property. Nevertheless, it is their burden to prove same. If you have not done so, you may wish to have a will prepared, as I venture it is not your intent for your siblings to have any interest in your estate.
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