Leaving Rental Income in a Last Will.

Dear Sir/Madam, I hope this letter finds you well. I am writing to seek clarification on matters related to inheritance and taxation within the United Kingdom. Specifically, I have a number of questions concerning the distribution of rental property income and the associated tax implications. The situation in question revolves around the last will and testament of an individual who wishes to allocate rental income from properties to their long-term partner, with the ownership of these properties to be passed on to their two sons, and upon the death of the partner, the rental income to then be passed to the 2 sons. I am interested in understanding the legality and tax implications of the following scenarios: 1. Can an individual legally designate in their will that rental income from properties goes to their long-term partner, who is not an owner of the properties? If so, how would the income be taxed when received by the partner? 2. Is it necessary for the two sons, who are the exclusive owners of the properties, to receive the rental income and pay the associated tax, given that they are the legal owners of the property, while the partner has no legal ownership or financial stake in the properties other than being designated to receive the rental income for her lifetime, as specified in the will? Is it legal or permitted for the partner to declare the rental income on her own self assessment and for her to pay the income tax, rather than the sons? 3. Additionally, the will grants the partner the use of a small flat for her lifetime, which she may choose to live in or rent out for income. Would there be any tax implications, such as a "benefit in kind," related to her living in the flat rent-free? If possible, please provide references to relevant statutes or regulations, or direct me to any forms or procedures that should be followed. Thank you for your time and attention. I look forward to your response.

Hi Franco,
We cannot reply to letters via this forum and you have posed questions that are about your own situation.
I would therefore suggest that you write to HMRC for a more detailed response. Please note however that we cannot comment on the legality of a will and you will
need to seek independent advice on this matter.
Guidance on settlement legislation is covered in the Trust Settlements and Estates Manual at TSEM4000 onwards. TSEM4000 - Settlements legislation
f you cannot find the answer to your question you can contact the Trust Office on 0300 123 1072.
Ownership of property comprises legal ownership (TSEM9120) and beneficial ownership (TSEM9130).
The same person may be both legal owner and beneficial owner of the property, but there can be a separation of the two.
The legal owner is the person/s in whose name/s the property is held or registered. The beneficial owner is the person for whose benefit the property is held.
It is distinguished from the person in whose name the property is held (the legal owner). The starting point is that the legal owner is presumed to be the beneficial
owner unless there is evidence to the contrary. The legal and beneficial ownership of property may be separated by a valid declaration of trust.
Further information is available at: TSEM9150 - Ownership and income tax: legal background: ownership: legal and beneficial ownership - separation - 
Thank you.