I thank all the good punctuation faeries in advance.

A line from my current WIP (actually two, the first is to put it in context, in case that matters):

"You might want to save some [popcorn] to make garlands for your tree," Dad said.

"Yes, that too," I replied. [Comma after that?]

I normally put a comma after the word preceding 'too.' But it looked odd to me this time. I've put it in and taken it out several times now. Word doesn't seem to care.