I would guess that his name changes would have been informal and for convenience.
We now have two birthdays for sister Maya, two hospitals where obama was born...and all we know about marriages, divorce and adoption are from the same source - obama's books.
I'm reminded that arab muslims can rid themselves of an unwanted wife by declaring three time 'I divorce thee' - perhaps the same applies to marriage and adoption. 'I adopt three' three times - 'I marry thee' three times, LOL!
One thing is quite clear. Whilst we assume muslims follow the same rules and regulations we do, fill in the same forms etc, we are only showing how little we know about islam. To follow our rules is against their 'religion' - our laws are infidel laws.
The only time a muslim follows 'infidel' rules is when there's a benefit, and come to think of it, any forged document will do for that.