I thought this was a very charming episode for the show, with Claire being lovably tormented by her family over her turning of 46, one of my favorite jokes involving the "Coz" putting up a sign that says "happy 64 birthday", and when she points it out he apologizes and flip the 6 upside down so it says "94".
What really makes this a charming episode though is the end. With a very long sequence after Claire aluding to one of Heathcliffs more common torturings where he buys here a whole cake and watches her eat it and that she was "glad he didnt do it this year." So Heathcliff puts on a jazz record, walks into the kitchen, and comes out with the cake. Then, he leaves and comes back in with a second cake, and then a third. All the while miming humorouse "ooooohh take this" motions at her. It's very charming and it required no speaking at all.
Like i said a very special episode all around, filled with classic Cosby humor.