stick in with someone —(coll.) join another person as a companion (to share accommodation, etc.):
- My mother wants me to stick in with my uncle, who has no children of his own.
stick with someone —(coll.)
1. (also: stick to someone) remain loyal to a person; stay close (in the face of danger, etc.):
- Stick with the gang on those beach parties. There’s safety in numbers.
2. (Races) remain level with a competitor:
- Jim was able to stick with the leading runner for most of the race.
3. continue to pay attention to what a person says:
- Stick with me for a few more minutes and you’ll see the point.