I feel I do not understand your Question at all, we are presently in 2015. What is about the year 2022.
If what you want to know that in 2022 the dasha of the boy and girl are changing within 4 months , then is it good or bad for their health. First of all where did you read that the dasha change as suggested by you is bad. Some dasha from birth dasha are bad, but that is a totally different concept.
Secondly just want to let you know it is the dasha of functional malefic planets that will be bad, but death will be in the period of Maraka dasha and bhadaka planet has to be involved. Therefore if you feel that a change in dasha in the span of 4 months will bring death to the boy or the girl then it is not there.