Sister visiting the UK visa refusal

My sister is in India, before that she was in the UK on student visa but due to health issues she wasn't able to attend her course to the end of the term and was working less than 15 hours a week to pay off her living cost. After few months she decided to go back to India well before her student visa expired genuinely to get a proper treatment for her health problems mainly because her doctor was in India and having my mother around was another support for her.

Now she is better and just wanted to spend some time with me and my two kids (I am married, both me & my husband are British citizen, own a house, working full time). During her stay due to health problems she was unable to spend time with us and hence applied for a visit visa. Her visa has recently been refused on the grounds that she may not return back to India. She is running her own beauty salon and has three employees who can look after her business in her absence for 3-4 weeks. She was also given a note that her Income Tax returns submitted in India are self-certified which seems to be not correct as I have copies clearly indicating certified by a Chartered Accountant with the membership number.

Please advise- is it okay to reapply from the UK? Anything that can help me to get my sister before my birthday by the end of this month so I can spend some valuable time with her. It is expensive for me and my family to travel to India!

She is married and her husband is in India (he is not visiting though), if this info helps!

Wordings on refusal letter;

-You stated you are the owner of a hair & beauty parlour & your income is Rs 24,500 per mth. You have submitted a un translated certificate of establishment & a self written letter on a letter headed paper. I note that you have submitted tax returns, however these are self prepared. I must consider your application for a visit visa and from the documents you have provided you have not established that your circumstances are as claimed.

-I note that you previously had leave to remain as a student, however Head office records show this leave was curtailed inJune 2011 as you did not attend classes. During an interview with you confirmed that you had not attended classes since start 2011. You stated that you did not attend classes as you were unwell, however you continued to work during this time. You stated that you did not return to India when you became unwell and stopped attending college as your family wanted you to continue treatment however your doctor was in India and that you did not have a GP in the UK. Whilst I note that you voluntarily returned to India in January 2013.

In light of the above and you stayed in the UK after your leave was curtailed this leads me to doubt that your intentions are as stated. I am therefore not satisfied that you intend to leave the UK at the end of your visit or that you are genuinely seeking entry as a visitor for a period not exceeding 6 months (paragraph 41(i)(ii) of HC 395 as amended).