Long johns - how much should I size up?

[jess_g]

My son wears a size 6 pants and a size 5T or 5/6 shirts. I just bought him some long john PJs from Talbots kids in size 6 (the only ones they had that were on sale). They are very cute but I think they may be just his size. Should I return them and get him a pair in a bigger size? Will they shrink much?

Thanks,

Jessica.

[newmomto3kids]

I always go up at least a size or two. My 4 year old is in size 6, my 2 year old is in size 3 and my soon to be 6 year old has them as big as size 10. They do tend to shrink a little, and I always find they are on the small side as well.
But, for the record, I do believe they are supposed to be snug fitting to increase the flame resistance.