Use of the form is optional. If the letter contains all the details required, that's fine. If there is still time, you can ask her to sign the form and send it to you.My mother-in-law is offering to let us live with her indefinitely and has sent us a letter stating that, as well as the appropriate supporting documents for my visa application. However, I just noticed a form mentioned - "Sponsorship Undertaking Form SU07". Is that something I should have downloaded and had her sign since she is offering to house us?
Yes. Also if it's a permanent or fixed-term contract. It has to be on the company's official stationery.And another letter question - what should the letter from my husband's future UK employer include? Just that they are offering a position, how much the salary per annum will be, etc.?