Congratulations! More Money, better conditions, only one job instead of two to handle is always good!
OTOH, wouldn't be too hard on the boss. Clearly, she didn't feel close enough to him to clue him in on her emergency leave earlier. As long as the birth went okay, many people would think "no news is good news."
I had an excellent relationship with my former boss, and in sixteen years he never, ever called me at home to find out how anything was. I did take a leave of absence once. I told him in March I might have to do that at some point in the future. I told him when I left for vacation in November that I might need that leave and be gone longer than a week. My husband called him eight days after I left and told him I'd be back in December. He said to my husband, "If Nonesuch needs a leave of absence, she'll have one." He never even asked why. I reappeared in December, and not one word was said. He wasn't my friend, he was my boss, and a good one, too. He paid my full salary the three extra weeks I was gone.
I think Miss Manners said, "Your friends at work are the people you would still see if one of you got fired."