Nepal and Bhutan as part of India

Is there any way that Nepal and Bhutan could become part of a united India?
Would it take longer colonial rule?
Simply different choices (can be pre-1900 if it needs to be, but not before 1858)
Or a successful revolt (you can use any way how this revolt might start. Germany winning WW1, worse Colonial rule or simply Britain having less power to govern India)?
For Nepal, Just have Britain Conquer them or have them as princely states, For Bhutan, there is no PODs required, India can pretty much annex them like Sikkim if they want,