I heard Jack Hanna on TV last night talking about this. What he said was it was possible that at least some of the cubs that Cecil’s “brother” is protecting could have been fathered by him and not Cecil or that even if the paternity is in question, even those cubs having been fathered by Cecil, that Cecil’s brother would recognize the cubs as being more closely genetically related to him (I’m guessing by scent or appearance?) than to the other male lions in the pride who want to take it over and hence have a biological instinct to protect the bloodline. I thought that was interesting.
I guess not everyone saw “The Lion King”. Those cubs (at least the boys) better enjoy it now. And the following article seems to agree with Hanna (”lions can’t be stepfathers” last paragraph).
http://www.livescience.com/41572-male-lion-survival.html
Excerpt:
“The lion cubs seem happy and carefree, but their lives are not easy. Only about 1 in 8 male lions survive to adulthood, Dereck said...
But when male lions begin to reach sexual maturity around age 2, the older males within the pride kick them out, Dereck said. The female lions, which are usually all related to some degree, typically stay behind.
For a young male, “the betrayal by his own blood must be confusing to him, but this is an ancient rite — the casting out of young males into a world of unknowns — a world where he will be able make it, or die,” ....
After being kicked out, the young males roam the countryside solo or in small bands, often with their brothers or cousins, negotiating the no-cat’s-land between territories of other lions...A majority of male lions die during this time...
When male lions take over a new territory, they almost always kill the prides’ cubs, since they are not biologically related and do not want to spend energy ensuring that other lions’ genes will be passed on. “They can’t be stepfathers,” Hunter told LiveScience. Female lions also will not be receptive to mating while they are nursing, so killing the cubs enables the male lions to procreate, said Beverly....
Years ago they had mutual of omaha animal shows on tv where one learned about this.