How often does/did your eight month old nap?

I have been having some concerns that my eight month old is sleeping too much. It's not affecting his development whatsoever, but he's napping a lot and has been for the last month or so. He gets up in the morning around 7 (after sleeping all night long), nurses, has breakfast, plays and then goes back down at about 8:00 until about ten. He then takes another nap around 12:30 until about 1:30- 2 ish... then another one at 4 for about a half hour and then another one at 6:30 for about an hour and then goes down for the night around 9- 9:30. I have tried everything to keep him awake, but he gets fussy and cries and tugs his ear rubs his eyes... I am at a loss as to what to do. His pediatrician says it's alright as long as he's developing fine, it's nothing to worry about, but of course I'm still going to worry about it. I have another child (3 years), but she was not a napper.