I THINK they can reabsorb....or hold feotii back from developing.
I'd say they have a different, but pragmatic, view.
Bad roo mummies kind of commit infanticide a lot, through not protecting their kids well enough.
Good roo mummies rear a LOT of theirs.
There's a great doco of them, called Faces in the Mob, exploring their social structure.
Last year we spent time with friends near Pt Macquarie in NSW, who live in a very rural environment.
They have a mob of roos living pretty much on their land, which spend a great part of their day relaxing on the lawn, and being roos.
It was great, because we saw one of the big males come in and find someone in oestrus...so we saw courtship, chasing the other boys away, and suchlike.
Australians will be stunned to know that courting males make a very Skippy-like noise!