Justeen Fellows, whose family member lives in the property but wished to remain anonymous, reported the disrepairs to Sandwell Council and received a response she described as "disgusting".
The tenant has a long-term condition which causes widespread pain, fatigue and mental health problems.
Ms Fellows, aged 37 and from Tipton, said: "There hasn’t been a trigger event as such, but we have noticed leaks on the wall and damages to her curtains on and off over the years.
“Often the repairmen, who I can’t fault as they have been so lovely, have sealed her windows, but the leak is still coming through. But clearly that hasn’t worked because the damage is getting worse and worse. We thought as a family we have to get involved now, because it is absolutely ridiculous the position we are in.
“We are disgusted with this treatment by Sandwell Council. We wouldn’t have that for four years, so why hasn’t an organisation as big as Sandwell Council found a solution to our problem?”
Ms Fellows claimed the problem is not from the lack of seal in the windows themselves, but with the lintel, which is seeping water into the house.
“The plaster was peeling away so bad that we had to completely strip the wall bare and expose the brickwork,” she said.
Even while curtains, lino, carpets, and blinds, have been damaged by the waters, Ms Fellows claimed the council would not pay for any of the damages.
“They wouldn’t even bring out a bucket for her to catch the leaks when we requested one.
“In the run up to Christmas, the leakage got very bad. When we tried to phone an emergency repairs number listed on their website, they would not issue a repairman out, as it was already logged as an ‘ongoing repair’ in their system.”
She added the prospect of her family member – who has fibromyalgia – living in the damp conditions was "terrifying" and said it was difficult for her to move, let alone try to repair something.
"I feel like she has given up the ghost. She loves decorating her home, and is so proud of it, but now she doesn’t know what to do," she said.
The problem, Ms Fellows believes, lies with the management in Sandwell Council. In an email, Ms Fellows spoke to the leader of Sandwell Council, Kerrie Carmichael to air her concerns – and said the response was "extremely frustrating".
Councillor Carmichael explained the reasons for delays to the repairs were due to “materials and a further item that is in the process of being made”. In the email she noted the repairmen, who are “experienced craft persons in their trade”, were unable to detect the source of the leak.
A spokesperson for Sandwell Council said: “We are very sorry that Ms Fellow’s (family member) has experienced issues with a leak and the council is working hard to resolve the problem.
“We have carried out work on various occasions, and on December 8 we removed the external UPVC moulding and sealed the gap under the window sill that has been causing the rain to leak into the property. We have also drilled some small holes to allow the water to run outside rather than into [redacted] ceiling.
“We will be replacing the living room window to the flat above, to allow for further exploratory works to eradicate the water penetration. We will be replacing the window in the upstairs flat as soon as possible in January, as well as replacing the window in the flat.
“Once this work is complete, appointments will be made to carry out the plastering and decorations. Hopefully these actions will resolve the problem.
“We apologise again for the inconvenience the leak has caused.”
Councillor Scott Chapman, an opposition Conservative representative, called for an investigation.
He said: “It is completely unacceptable that Ms Fellow’s (family member) is still waiting for a proper repair for over four years.
“The council must undertake a full investigation into the cause of the leak to ensure that the next fix is a permanent one rather than a series of bodge jobs and this needs to be done as a matter of urgency so that [redacted] is no longer left in the lurch."