Who's to say he didn't get a new number for the droid and kept his old phone with the old number - you didn't say whether you even tried dialing the old number.
Sorry, while the rant for him not contacting to find out how his daughter is a valid one. Have no clue how the realtionship between the two of you is, but if the rest of the rant gives any indication (hangin' up the phone, yada, yada, yada) - no comment.
P.S. - I do hope your daughter is recovering well...