Defying gravity

I got a bouquet of helium-filled balloons for Andrew's birthday party four weeks ago. (Has it really been four weeks? I should really get started on those thank-you cards.) I paid extra for something called Hi-Float, which promised to make the balloons float for a week! Well, they all made it three weeks, which is amazing, and several made it to this weekend, but now the remaining few are running out of hot air, so to speak. When each one started to droop on its ribbon, I cut it loose and let it float free, so it could drift through the apartment, carried along by whatever faint airflow it got caught up in. It would suddenly appear next to my head or wander off down the hall for no apparent reason. Then, slowly, it would start to hover lower to the ground, until, finally, it could float no more, although when tossed it would glide downward in slow motion, still bending the rules of gravity just a little. Right now, only one is still up, floating against the ceiling in the corner, while two are standing on their knots on the ground, not quite ready to lie flat.

I feel like there's a metaphor in here somewhere.