Arrangements are different in Scotland, and in England. You need to check which apply to you.
Residential care costs here are around £2000 per week.
£100,000 pa. You should take a look around local care homes to see what's available.
If taken into residential care, your finances will be assessed. If you were unable to self- pay, the costs would accumulate to be claimed (after you die) as a debt from your estate , before any other bequests in your Will.
If your house is your main asset, it could then be sold to cover the care debt. Depending on house value, and size of debts, that might drain your assets dry leaving little or no inheritance for either child; and your son homeless.