I have Tolsimir Wolfblood on the field and Rhys, the Redeemed
Does Rhys get +1/1 or +2/2?
It is green and it is white, so it gets both bonuses.
Actually, the issue doesn't lie in Rhys's coulours but in the fact that Tolsimir has two separate abilities, if it were worded like this, Rhys wouldn't get +2/+2 but +1/+1: Green and white creatures you control get +1/+1.
Rules question? Have you read the Basic rulebook already? No? Why not take some time to do that?