I used to work in this field and would suggest that anyone considering making any changes to property ownership should seek specialist legal advice.
In respect of your situation Tracey, your mother is completely safe, the house will not be taken into consideration so long as she lives there. If she required residential care as well then the house would need to be sold to pay for both of your parent's fees unless they had enough savings / income not to need to (in some cases, the property can be rented to top up an income.
If your mother gifts the property to someone to avoid it being used to pay care home fees, this could be considered to be 'deprivation of assets', and the beneficiary would become wholly responsible for the fees. There is, contrary to popular belief no timescale for this!
On another point which may or may not be relevant in this case, is if your relatives care is to be funded by the local authority, (either from the outset or when their savings have dropped), the local authority will inform you of the maximum fee that they are prepared to pay. Frequently, it will be difficult to identify a bed available within the amount, or the home that is particularly liked will be more expensive.
In these circumstances a 'third party top up' will need to be agreed. In this situation, the LAW does not allow the savings of the resident to be used to top up the fees.
It is also VERY important that when agreeing a third party top up, an agreement is made about future fee increases. The responsibility of the third party should be to pay the incremental % increase. So for example if the third party is responsible for a top up of 10% of the total weekly fee, any increase in fees that they become liable for should represent 10% of increase.
Finally, if your loved one is responsible for funding their own care, it is important that they claim all their entitlements. This would include Attendance Allowance, FLA or the new Personal Independence Payment, and in the event that they are on a low income, it might be worth making a claim for Pension Credit......I have known elderly people with savings of £60k+ on very low incomes who had some entitlement to means tested benefit.