Too Old for This? Exersaucer Fun (video)

I've been trying to clear out junk out of storage for some time now.  We stored this exersaucer in the garage for over a year and pulled it out to sell.  After I cleaned it down, we put it into the living room and all 3 kids wanted to play with it!  The young one wanted to sit in it and would not get out.

Isn't it too small for him?  (normally for infants who are 9 months old)  Apparently not.  He played with it 3 nights in a row, for over 15 minutes each time.