your sister is running Mahadasha of lagna lord Jupiter since 24/1/2016 and Jupiter is placed in 8th house in Chalit with 9th lord Sun in nakshtra of Ketu with moon as sublord.
Seems like she is seeing someone and I see her relation intensifying from 29/7/2017 in Jup-Jup-Moon period (she will have an above average married life). Transit of Jupiter to 11th house from 12 Sep 2017 is conducive for marriage and good chances of marriage exist during Jup-Jup-Rah period from 16/11/2017 to 13/3/2018. Otherwise Jup-Sat-Mer period from 6/8/2018 will open the doors again for marriage.
Chances of going abroad are better from 2020 onwards.